Assessment of the yellowfin stock in the Bering Sea and Aleutian Islands Thomas K. Wilderbuer, Daniel G. Nichol and James Ianelli

Executive Summary Summary of Changes in Assessment Inputs Changes to the input data 1) 2016 fishery age composition. 2) 2016 survey age composition. 3) 2017 trawl survey point estimate and standard error. 4) Estimate of the discarded and retained portions of the 2015 catch. 5) Estimate of total catch made through the end of 2017. Catch of 150,000 t assumed for 2018 and 2019 projection. Changes to the assessment methodology No changes were made to this assessment. Summary of Results The assessment updates last year’s with results and management quantities that are higher than the 2016 assessment primarily due to 1) including 2016 fishery weight-at-age information, 2) including two more years in the spawner-recruit time-series, and 3) a lower estimated survey catchability. Yellowfin sole continue to be well-above BMSY and the annual harvest remains below the ABC level. The female spawning stock is in a slow downward trend. As estimated or As estimated or specified last year for: recommended this year for: Quantity 2017 2018 2018 2019 M (natural mortality rate) 0.12 0.12 0.12 0.12 Tier 1a 1a 1a 1a Projected total (age 6+) biomass (t) 2,290,000 2,202,300 2,553,100 2,460,700 Female spawning biomass (t) Projected 778,600 770,900 895,000 890,000 B0 1,202,700 1,204,000 BMSY 424,000 456,000 FOFL 0.125 0.125 0.12 0.12 maxFABC 0.114 0.114 0.109 0.109 FABC 0.114 0.114 0.109 0.109 OFL (t) 287,000 276,000 306,700 295,600 maxABC (t) 260,800 250,800 277,500 267,500 ABC (t) 260,800 250,800 277,500 267,500 As determined last year for: As determined this year for: Status 2015 2016 2016 2017 Overfishing No n/a No n/a Overfished n/a No n/a No Approaching overfished n/a No n/a No Projections are based on estimated catches of 150,000 t used in place of maximum ABC for 2018 and 2019.

Responses to SSC and Plan Team Comments on Assessments in General General comments for all assessments:

SSC encourages assessment authors to adopt the current model naming convention.

This assessment now complies with the desired naming convention.

Responses to SSC and Plan Team Comments Specific to this Assessment The yellowfin sole stock assessment has set an example for its inclusion of ecosystem factors in the assessment. Temperature was found to be related to survey catchability and growth. Interestingly, after conducting a field experiment to further examine relationships between temperature and catchability, it was found that survey biomass is more strongly correlated to wave height than temperature, which is in turn confounded with temperature. The SSC supports the approach outlined in the SAFE to further elucidate the effects of sea state and/or bottom temperature on q, noting that these covariates may act on the assessment in different ways (i.e., availability versus gear efficiency). If an effect of wave height on catchability is confirmed, implying that rougher seas adversely affect the ability of the trawl to tend the seafloor, then this would beg the question whether other assessed species are similarly affected. So, the outcome of this work has the potential for important, far-reaching implications.

The results of last summer's sampling efficiency experiment indicated that sea-state had a much larger effect on yellowfin sole herding, and trawl efficiency in general, than bottom temperature. Dan Nichol looked at the time-series of eastern Bering Sea yellowfin sole biomass estimates and found that they also were strongly correlated to wave height. To confuse things more, wave height was correlated to temperature.

1. The experimental results were analyzed and a paper on wave height effect on yellowfin sole catchability was submitted to Fisheries Bulletin (The effects of wave-induced vessel motion on the geometry of a bottom survey trawl and the herding of yellowfin sole by Somerton, Weinberg, Munro, Rugolo and Wilderbuer, In Review). However, this still does not answer the question of why you find a strong temperature effect on the survey catchability function in the stock assessment model. One possibility is that trawl sampling efficiency is more influenced by waves but yellowfin sole availability to the survey is more influenced by temperature.

2. Dan Nichol has completed a CPUE versus waves analysis back to 2005. Although RACE surveys have recorded sea state data for many years it was not entered into the database earlier than 2005, so Dan will do some hand entry, then repeat the analysis with more years and considering wave height and temperature together in a model. This work is viewed as secondary to the availability research (see #3), given that availability likely has a much greater influence on biomass estimates than sea- state/temperature.

3. Dan Nichol also has made progress toward showing that yellowfin sole availability changes with temperature using sex ratio, based on the notion that males arrive first and leave the spawning areas later than females, and that the timing of annual spawning is temperature-dependent.

4. A CIE review is scheduled for May 2018 for yellowfin sole, northern and Alaska . We will solicit comments from the expert panel on exploring an additional waves parameter to fit the survey biomass.

One ongoing issue with the yellowfin sole assessment is a strong retrospective pattern illustrated by Figure 4.21. More recent assessments tend to yield higher estimates of female spawning biomass. Attempts to determine the cause have been unsuccessful so far. The PT suggested that the author consider examining the potential effects of q and M on the retrospective patterns. The SSC encourages ongoing efforts to understand this phenomenon so that appropriate model adjustments can be made. The SSC also recommends updating weight-at-age with each assessment as new data become available annually. Finally, the SSC looks forward to the use of the adopted model naming convention in next year’s yellowfin sole assessment.

The retrospective comment is addressed in this assessment under the retrospective analysis heading. Weight-at-age is routinely updated, both for the fishery and the survey.

Introduction The yellowfin sole ( aspera) is one of the most abundant species in the eastern Bering Sea (EBS) and currently is the target of the largest flatfish fishery in the world. They inhabit the EBS shelf and are considered one stock. Abundance in the Aleutian Islands region is negligible. Yellowfin sole are distributed in North American waters from off British Columbia, Canada, (approx. lat. 49o N) to the Chukchi Sea (about lat. 70o N) and south along the Asian coast to about lat. 35o N off the South Korean coast in the Sea of Japan. Adults exhibit a benthic lifestyle and occupy separate winter, spawning and summertime feeding distributions on the eastern Bering Sea shelf. From over-winter grounds near the shelf margins, adults begin a migration onto the inner shelf in April or early May each year for spawning and feeding. The directed fishery has typically occurred from winter through autumn (Wilderbuer et al. 1992). Yellowfin sole are managed as a single stock in the BSAI management area as there is presently no evidence of stock structure.

Fishery Yellowfin sole have annually been caught with bottom trawls on the Bering Sea shelf since the fishery began in 1954 and were overexploited by foreign fisheries in 1959-62 when catches averaged 404,000 t annually (Fig. 4.1, top panel). As a result of reduced stock abundance, catches declined to an annual average of 117,800 t from 1963-71 and further declined to an annual average of 50,700 t from 1972-77. The lower yield in this latter period was partially due to the discontinuation of the U.S.S.R. fishery. In the early 1980s, after the stock condition had improved, catches again increased reaching a peak of over 227,000 t in 1985. During the 1980s, there was also a major transition in the characteristics of the fishery. Yellowfin sole were traditionally taken exclusively by foreign fisheries and these fisheries continued to dominate through 1984. However, U.S. fisheries developed rapidly during the 1980s in the form of joint ventures, and during the last half of the decade began to dominate and then take all of the catch as the foreign fisheries were phased out of the EBS. Since 1990, only domestic harvesting and processing has occurred. The management of the yellowfin sole fishery changed significantly in 2008 with the implementation of Amendment 80 to the BSAI Fisheries Management Plan. The Amendment directly allocated fishery resources among BSAI trawl harvesters in consideration of their historic harvest patterns and future harvest needs in order to improve retention and utilization of fishery resources by the non-AFA trawl catcher/processor fleet. This was accomplished by extending the groundfish retention standards to all H&G vessels and also by providing the ability to form cooperatives within the newly formed Amendment 80 sector. In addition, Amendment 80 also mandated additional monitoring requirements which included observer coverage on all hauls, motion-compensating scales for weighing samples, flow scales to obtain accurate catch weight estimates for the entire catch, no mixing of hauls and no on-deck sorting. The partitioning of TAC and PSC (prohibited species catch) among cooperatives has significantly changed the

way the annual catch has accumulated (Fig 4.1, bottom panel) and the rate of target catch per ton. There is now a more even and slow attainment of the annual catch relative to the pre-Amendment 80 fishing behavior. Yellowfin sole are usually headed and gutted, frozen at sea, and then shipped to Asian countries for further processing (AFSC 2016). The first wholesale value of Alaska yellowfin sole totaled $97.8 million in 2014. In 2010, following a comprehensive assessment process, the yellowfin sole fishery was certified under the Marine Stewardship Council environmental standard for sustainable and well-managed fisheries. The certification also applies to all the major flatfish fisheries in the BSAI and GOA. The total annual catch (t) since implementation of the MFCMA in 1977 is shown in Table 4.1. In 2011, federally permitted vessels using non-pelagic trawl gear whose harvest results in flatfish retained catch that is greater than any other retained fishery category were required to use modified trawl gear. The modifications required the use of elevating devices to raise the section of the trawl warps between the doors and the trawl wing tips by 2.5 inches off the seafloor. The purpose of the management action was to reduce damage of non-target , particularly those that form habitat structure or support other fisheries while not substantially reducing flatfish catch rates or causing gear handling problems (Rose et al. 2010). The 1997 catch of 181,389 t (retained and discards) was the largest since the fishery became completely domestic but was at lower levels from 1998 – 2010, averaging 94,004 t (Table 4.2). From 2011-2014 the catch increased, averaging 155,000 t. The 2013 catch totaled 165,000 t (73% of the ABC), the highest annual catch in the past 19 years. For 2017, the catch distribution has been spread out from January through May with the majority coming from 4 BSAI management areas (509, 513, 514, 516). As of mid- October 2017, the fishing season is ongoing. In order to estimate the total 2017 catch for the stock assessment model, the average proportion of the 2010-2016 cumulative catch attained by the 37th week of the year (mid-September) was applied to the 2017 catch amount at the same time period and results in a 2017 catch estimate of 143,100 t (55% of the ABC). The size composition of the 2017 catch for both males and females, from observer sampling, are shown in Figure 4.2, the catch proportions by month and area are shown in Figure 4.3, and maps of the locations where yellowfin sole were caught in 2017, by month (through mid-September), are shown in Figure 4.4. The average age of yellowfin sole in the 2016 catch is estimated at 12.9 and 12.3 years for females and males, respectively. The time-series of catch in Table 4.1 also includes yellowfin sole that were discarded in domestic fisheries during the period 1987 to the present. Annual discard estimates were calculated from at-sea sampling (Table 4.2). The rate of discard has ranged from a low of 2% of the total catch in 2012 (and 2015) to 30% in 1992. The trend has been toward fuller retention of the catch in recent years, and with the advent of the Amendment 80 harvest practices, discarding is at its lowest level since these estimates have become available. Historically, discarding primarily occurred in the yellowfin sole directed fishery, with lesser amounts in the , Pollock, rock sole, flathead sole, and “other flatfish” fisheries (Table 4.3).

Data The data used in this assessment include estimates of total catch, bottom trawl survey biomass estimates and their attendant 95% confidence intervals, catch-at-age from the fishery, and population age composition estimates from the bottom trawl survey. Weight-at-age and proportion mature-at-age are also available from studies conducted during the bottom trawl surveys.

Data source Years

Fishery catch 1954-2017

Fishery age composition 1964-2016 Fishery weight-at-age Avg wt at age from 2008-16 used for 2008-2016 Survey biomass and standard error, bottom temperature 1982-2017 Survey age composition 1979-2016 Annual length-at-age and weight-at-age from surveys 1979-2016 Maturity at age Combined 1992 and 2012 samples

Fishery Catch and Catch-at-Age This assessment uses fishery catch data from 1955- 2017 (shown for 1964-2017 in Table 4.1), including an estimate of the 2017 catch, and fishery catch-at-age (proportions) from 1964-2016 (Table 4.4, 1975- 2016). The 2016 fishery age composition was primarily composed of fish older than 9 years with a large amount of 20+ fish. Survey Biomass Estimates and Population Age Composition Estimates Indices of relative abundance available from AFSC surveys have shown a major increase in the abundance of yellowfin sole during the late 1970s, increasing from 21 kg/ha in 1975 to 51 kg/ha in 1981 (Fig. 4.2 in Bakkala and Wilderbuer 1990). These increases have also been documented through Japanese commercial pair trawl data and catch-at-age modeling in past assessments (Bakkala and Wilderbuer 1990). Since 1981, the survey CPUEs have fluctuated widely (Fig. 4.5). Biomass estimates for yellowfin sole from the annual bottom trawl survey on the eastern Bering Sea shelf are shown in Table 4.5 and Figure 4.6. The data show a doubling of survey biomass between 1975 and 1979 with a further increase to over 3.3 million t in 1981. Total survey abundance estimates fluctuated erratically from 1983 to 1990 with biomass ranging from as high as 3.5 million t in 1983 to as low as 1.9 million t in 1986. Biomass estimates since 1990 indicate an even trend at high levels of abundance for yellowfin sole, with the exception of the results from the 1999 and 2000 summer surveys, which were at lower levels. Surveys from 2001-2005 estimated an increase each year but the estimates since 2006 indicate a stable level with some annual variability. However, the 2012 estimate is a 19% decrease from 2011 and the 2013 and 2014 surveys have estimated a 17% increase over 2012. Similarly, there was a 24% decrease from 2014 to 2015 followed by a 48% increase from 2015 to 2016, the highest biomass estimate since 1984. Fluctuations of the magnitude shown between 1980 and 1990, 1998 and 1999, 2008 and 2009, 2011and 2012, 2014 and 2015 and 2015 and 2016 are unreasonable considering the elements of slow growth and long life span of yellowfin sole combined with low to moderate exploitation rate, characteristics which should produce more gradual changes in abundance. Variability of yellowfin sole survey biomass estimates (Fig. 4.6) is in part due to the availability of yellowfin sole to the survey area (Nichol, 1998). Yellowfin sole are known to undergo annual migrations from wintering areas off the shelf-slope break to near shore waters where they throughout the spring and summer months (Nichol, 1995; Wakabayashi, 1989; Wilderbuer et al., 1992). Exploratory survey sampling in coastal waters of the eastern Bering Sea during early summer indicate that yellowfin sole concentrations can be greater in these shallower areas not covered by the standard AFSC survey than in the survey proper. Commercial bottom trawlers have commonly found high concentrations of yellowfin sole in areas such as near Togiak Bay (Low and Narita, 1990) and in more recent years from Kuskokwim Bay to just south of Nunivak Island. The coastal areas are sufficiently large enough to offer a substantial refuge for yellowfin sole from the current survey.

Over the past 18 years, survey biomass estimates for yellowfin sole have shown a positive correlation with shelf bottom temperatures (Nichol, 1998); estimates have generally been lower during cold years. The 1999 survey, which was conducted in exceptionally cold waters, indicated a decline in biomass that was unrealistic. The bottom temperatures during the 2000 survey were much warmer than in 1999, and the biomass increased, but still did not approach estimates from earlier years. Average bottom temperature and biomass both increased again during the period 2001 – 2003, with the 2003 value the highest temperature and biomass observed over the 22 year time series up to that time. Given that both the 1999 and 2000 surveys were conducted two weeks earlier than previous surveys, it is possible that the time difference may also have also affected the availability of yellowfin sole to the survey. If, for example, the timing of peak yellowfin sole spawning in nearshore waters corresponded to the time of the survey, a greater proportion of the population would be unavailable to the standard survey area. This pattern was observed again in 2009 and 2012 when the temperatures and the bottom trawl survey point estimates were lower. Summer shelf bottom temperatures in 2012 were the 2nd coldest recorded by the survey and the time-series and resulted in a 19% decline from 2011. In 2016 the Bering Sea had the highest recorded bottom temperature since measurements began in 1982 and the 2016 estimate of biomass was the highest in 32 years and 48% higher than the 2015 estimate. The 2017 survey estimate of 2,787,700 t was 3% lower than 2016. We propose two possible reasons why survey biomass estimates are lower during years when bottom temperatures are low. First, catchability may be lower because yellowfin sole may be less active when cold. Less active fish may be less susceptible to herding, and escapement under the footrope of survey gear may increase if fish are less active. Secondly, bottom temperatures may influence the timing of the inshore spawning migrations of yellowfin sole and therefore affect their availability to the survey area. Because yellowfin sole spawning grounds include nearshore areas outside the survey area, availability of fish within the survey area can vary with the timing of this migration and the timing of the survey. In the case of 2016, a very warm year in the Bering Sea, it appears that a higher portion of the adult biomass was distributed on the shelf (outside of the spawning areas) relative to the average of all previous survey years, indicating earlier spawning migration (Fig 4.7). Yellowfin sole population numbers-at-age estimated from the annual bottom trawl surveys are shown in Table 4.6 and their occurrence in trawl survey hauls and associated collections of lengths and age structures since 1982 are shown in Table 4.7. Their total tonnage caught in the resource assessment surveys since 1982 are listed in Table 4.8 and also in an appendix table with IPHC survey catches. Age Determination

Yellowfin sole ages have been determined at the AFSC by using the break and burn method on collected otoliths since 1979 in surveys and from fisheries. In 2016 the age determination methods for yellowfin sole were validated using the bomb-produced uptake measurement of 14C method (Kastelle et al. 2016). Length and Weight-at-Age Past assessments of yellowfin sole have used sex-specific, time-invariant growth based on the average length-at-age and weight-at-length relationships from the time-series of survey observations summed over all years since 1982. These weight-at-age estimates were estimated from the following relationships: Parameters of the von Bertalanffy growth curve have been estimated for yellowfin sole, by sex, from the trawl survey database as follows:

Linf K t0 n Males 33.7 0.161 -0.111 656 Females 37.8 0.137 0.112 709

A sex-specific length-weight relationship was also calculated from the survey database using the usual power function, weight (g) = a Length(cm)b, where a and b are parameters estimated to provide the best fit to the data (Fig. 4.8).

a b n males 0.00854 3.081 2,701 females 0.0054 3.227 3,662

These estimates of weight at length were applied to the annual trawl survey estimates of population length at age, by sex, to calculate the weight at each age (Fig. 4.8). Since the resulting estimates of annual weight-at-age were highly variable for fish older than 11 years, ages 11-20 were smoothed using a five year average smoothing method for 1982-2016.

Recent applications of dendrochronology (tree-ring techniques) have been used to develop biochronologies from the otolith growth increments of (Lepidopsetta polyxystra), yellowfin sole and (Pleuronectes quadrituberculatus) in the eastern Bering Sea. These techniques ensure that all growth increments are assigned the correct calendar year, allowing for estimation of somatic growth by age and year for chronologies that span approximately 25 years (Matta et al. 2010). The analysis indicated that yellowfin sole somatic growth exhibits annual variability and has a strong positive correlation with May bottom water temperature in the Bering Sea (Fig. 4.9). The relationship between temperature and growth was further explored by reanalyzing yellowfin sole growth by age and year. Length-weight data collected when obtaining otolith (age) samples in RACE surveys (n=7,000 from 1987, 1994 and 1999-2009) also indicate that weight at age exhibits annual variability and is highly correlated with summer bottom water temperature observations with a lag of 2-3 years for the temperature effect to be seen (shown for age 5 fish in figure 4.10) . These observations were then extended back to 1979 using survey population length-at-age estimates (since weight-at-age is a power function of the length-at-age, Clark et al. 1999, Walters and Wilderbuer 2000). In order to incorporate time-varying (year effect on growth) and temperature-dependent growth functions into the age-structured stock assessment model we used the annual observed population mean weight-at- age (time-varying) from the trawl survey. These empirical data indicate good somatic growth correspondence with annual bottom temperature anomalies from 1982-2017 (Fig. 4.11). Fishery weight at age data available from 2008-2016 were averaged across years for each age to provide updated estimates for the fishery Maturity-at-age

Maturity information collected from yellowfin sole females during the 1992 and 1993 eastern Bering Sea trawl surveys have been used in this assessment for the past 20 years (Table 4.10). Nichol (1995) estimated the age of 50% maturity at 10.5 years based on the histological examination of 639 ovaries. Maturity has recently been re-evaluated from a histological analysis of ovaries collected in 2012 (Table 4.10). Results were very similar to the earlier study with only a 2% difference in estimates of yellowfin sole female spawning biomass (TenBrink and Wilderbuer 2015). In addition, the SSC requested that the assessment use a maturity schedule that uses estimates derived from both the 1992 and the 2012 collections (Table 4.10). For yellowfin sole sexual maturity occurs well after the age of entry into the fishery. Yellowfin sole females are 82% selected to the fishery by age 10 whereas they have been found to be only 40% mature at this age.

Analytic Approach

Model Structure The abundance, mortality, recruitment and selectivity of yellowfin sole were assessed with a stock assessment model using the AD Model Builder language (Fournier et al. 2012; Ianelli and Fournier 1998). The conceptual model is a separable catch-age analysis that uses survey estimates of biomass and age composition as auxiliary information (Fournier and Archibald 1982). The assessment model simulates the dynamics of the population and compares the expected values of the population characteristics to the characteristics observed from surveys and fishery sampling programs. This is accomplished by the simultaneous estimation of the parameters in the model using the maximum likelihood estimation procedure. The fit of the simulated values to the observable characteristics is optimized by maximizing a log(likelihood) function given some distributional assumptions about the observed data. The model starts at age one and fish older than twenty are allowed to accumulate into a plus group. Since the sex-specific weight-at-age for yellowfin sole diverges after age of maturity (about age 10 for 40% of the stock) with females growing larger than males, the current assessment model is coded to accommodate the sex-specific aspects of the population dynamics of yellowfin sole. The model allows for the input of sex-specific estimates of fishery and survey age composition and weight-at-age and provides sex-specific estimates of population numbers, fishing mortality, selectivity, fishery and survey age composition and allows for the estimation of sex-specific natural mortality and catchability. The model retains the utility to fit combined sex data inputs. The suite of parameters estimated by the model are classified by three likelihood components: Data component Distributional assumption Trawl fishery catch-at-age Multinomial Trawl survey population age composition Multinomial Trawl survey biomass estimates and S.E. Log normal

The total log likelihood is the sum of the likelihoods for each data component (Table 4.11). The likelihood components may be weighted by an emphasis factor, however, equal emphasis was placed on fitting each likelihood component in the yellowfin sole assessment except for the catch. The AD Model Builder software fits the data components using automatic differentiation (Griewank and Corliss 1991) software developed as a set of libraries (AUTODIFF C++ library). Table 4.11 also presents the key equations used to model the yellowfin sole population dynamics in the Bering Sea and Table 4.12 provides a description of the variables used in Table 4.11. Sharp increases in trawl survey abundance estimates for most species of Bering Sea flatfish between 1981 and 1982 indicate that the 83-112 trawl was more efficient for capturing these species than the 400-mesh eastern trawl used in 1975, and 1979-81. Allowing the model to tune to these early survey estimates would most likely underestimate the true pre-1982 biomass, thus exaggerating the degree to which biomass increased during that period. Although this underestimate would have little effect on the estimate of current yellowfin sole biomass, it would affect the spawner and recruitment estimates for the time-series. Hence, the pre-1982 survey biomass estimates were omitted from the analysis. The model of yellowfin sole population dynamics was evaluated with respect to the observations of the time-series of survey and fishery age compositions and the survey biomass trend since 1982.

Parameters Estimated Outside the Assessment Model Natural mortality (M) was initially estimated by a least squares analysis where catch-at-age data were fitted to Japanese pair trawl effort data while varying the catchability coefficient (q) and M simultaneously. The best fit to the data (the point where the residual variance was minimized) occurred at

a M value of 0.12 (Bakkala and Wespestad 1984). This was also the value which provided the best fit to the observable population characteristics when M was profiled over a range of values in the stock assessment model using data up to 1992 (Wilderbuer 1992). Since then, natural mortality has been estimated as a free parameter in some of the stock assessment model runs which have been evaluated the past five years. A natural mortality value of 0.12 is used for both sexes in the base model presented in this assessment. Yellowfin sole maturity schedules were estimated from in-situ observations from two studies as discussed in a previous section (Table 4.10).

Parameters Estimated Inside the Assessment Model The parameters estimated by the model are presented below: Fishing Survey Year class Spawner- mortality Selectivity catchability strength recruit Total 65 264 2 104 2 437

The increase in the number of parameters estimated in this assessment compared to last year (6) can be accounted for by the input of another year of fishery data and the entry of another year class into the observed population and four more sex-specific fishery selectivity parameters. Year class strengths The population simulation specifies the numbers-at-age in the beginning year of the simulation, the number of recruits in each subsequent year, and the survival rate for each cohort as it moves through the population over time using the population dynamics equations given in Table 4.11. Selectivity Fishery and survey selectivity was modeled separately for males and females using the two parameter formulation of the logistic function (Table 4.11). The model was run with an asymptotic selectivity curve for the older fish in the fishery and survey, but still was allowed to estimate the shape of the logistic curve for young fish. The oldest year classes in the surveys and fisheries were truncated at 20 and allowed to accumulate into the age category 20+ years. A single selectivity curve, for both males and females, was fit for all years of survey data. Given that there have been annual changes in management, vessel participation and most likely gear selectivity, time-varying fishing selectivity curves were estimated. A logistic equation was used to model fishery selectivity and is a function of time-varying parameters specifying the age and slope at 50% f selection, ϕt and ηt , respectively. The fishing selectivity (S ) for age a and year t is modeled as,

−1 f ()a−ϕη tt ,ta []1+= eS where ηt and φt are time-varying and partitioned (for estimation) into parameters representing the mean and a vector of deviations (log-scale) conditioned to sum to zero. The deviations are constrained by a lognormal prior with a variance that was iteratively estimated. The process of iterating was to first set the variance to a high value (diffuse prior) of 0.52 and estimate the deviations. The next step was to compare the variability of model estimates. The variance of the model estimates were then rounded up slightly and fixed for subsequent runs. The 2016 values were fixed as the average of the 3 most recent years. Fishing Mortality The fishing mortality rates (F) for each age and year are calculated to approximate the catch weight by solving for F while still allowing for observation error in catch measurement. A large emphasis (300) was placed on the catch likelihood component to force the model to closely match the observed catch.

Survey Catchability A past assessment (Wilderbuer and Nichol 2001) first examined the relationship between estimates of survey biomass and bottom water temperature. To better understand how water temperature may affect the catchability of yellowfin sole to the survey trawl, catchability was estimated for each year in the stock assessment model as: = eq +− βα T where q is catchability, T is the average annual bottom water temperature anomaly at survey stations less than 100 m, and α and β are parameters estimated by the model. The catchability equation has two parts. The e -α term is a constant or time-independent estimate of q. The second term, eβT is a time-varying (annual) q which responds to metabolic aspects of herding or distribution (availability) which can vary annually with bottom water temperature. The result of incorporating bottom temperature to estimate annual q has resulted in an improved fit to the survey (shown in Figure 4.12 for the base model). Spawner-Recruit Estimation

Annual recruitment estimates from 1978-2012 were constrained to fit a Ricker (1958) form of the stock recruitment relationship as follows: −βS R = αSe where R is age 1 recruitment, S is female spawning biomass (t) the previous year, and α and β are parameters estimated by the model. The spawner-recruit fitting is estimated in a later phase after initial estimates of survival, numbers-at-age and selectivity are obtained. Results Model Evaluation

The model evaluation for this stock assessment involved a two-step process. The first step was to evaluate the productivity of the yellowfin sole stock by an examination of which sets of years to include for spawner-recruit fitting (increased from 1978-2010 to 1978-2012 in this assessment). The second step evaluated various hypothesized states of nature by fitting natural mortality and catchability estimates in various combinations. The SSC determined in December 2006 that yellowfin sole would be managed under the Tier 1 harvest guidelines, and therefore future harvest recommendations would be based on MSY and FMSY values calculated from a spawner-recruit relationship. MSY is an equilibrium concept and its value is dependent on both the spawner-recruit estimates which are assumed to represent the equilibrium stock size- recruitment relationship and the model used to fit the estimates. In the yellowfin sole stock assessment model, a Ricker form of the stock-recruit relationship was fit to various combinations of these data and estimates of FMSY and BMSY were calculated, assuming that the fit to the stock-recruitment data represents the long-term productivity of the stock. For this assessment, 2 different stock-recruitment time-series were investigated: the full time-series 1955- 2012 (Model 14_2) and the post-regime shift era, 1978-2012 (Model 14_1) (Fig. 4.13) (see Joint Plan Team recommendations for September 2012). Very different estimates of the long-term sustainability of the stock (FMSY and BMSY) are obtained, depending on which years of stock-recruitment data are included in the fitting procedure (Table 4.13). When the entire time-series from 1955-2012 was fit, the large recruitments that occurred at low spawning stock sizes in the 1960s and early 1970s determined that the yellowfin sole stock was most productive at a smaller stock size with the result that FMSY (0.19) is higher than F35% (F35% = 0.14) and BMSY is 333,700 (Model 14_2). If we limit the analysis to consider only recruitments which occurred after the well-documented regime shift in 1977 (Model 14_1), a lower value of FMSY is obtained (0.114) and BMSY is 456,200 t. Table 4.13 indicates that the ABC values from the

Model 14_2 harvest scenario for 2018 would be 193,800 t higher than Model 14_1. Posterior distributions of FMSY for these models indicate that this parameter is estimated with less uncertainty for Model 14_1 resulting in the reduced buffer between ABC and OFL relative to Model 14_2 (11% for Model 14_1 versus 1% for Model 14_2, Table 4.13 and Fig 4.14). It is important for the Tier 1 calculations to identify which subset of the stock recruitment data is used. Using the full time series to fit the spawner recruit curve estimates that the stock is most productive at a small stock size. Thus MSY and FMSY are relatively high values and BMSY is a lower value. If the stock was productive in the past at a small stock size because of non-density dependent factors (environment), then reducing the stock size to low levels could be detrimental to the long-term sustainability of the stock if the environment, and thus productivity, have changed from the earlier period. Since observations of yellowfin sole recruitment at low stock sizes are not available from multiple time periods, it is uncertain if future recruitment events at low stock conditions would be as productive as during the late 1960s-early 1970s. Given the uncertainty of the productivity of yellowfin sole at low spawning stock sizes, and because the AFSC policy for reference point time-series selection is to use the post 1977 regime shift values unless there is a compelling reason to do otherwise, the productivity of yellowfin sole in this assessment is estimated by fitting the 1977-2012 spawner-recruit data in the model (Model 14_1). The second step in the model evaluation for this assessment entails the use of a single structural model to consider the uncertainty in the key parameters M and catchability. This is the Model which has been the model of choice is the past 7 assessments (Model 14_1) and operates by fixing M at 0.12 for both sexes and then estimates q using the relationship between survey catchability and the annual average water temperature at the sea floor (from survey stations at less than 100 m). The other models used in the evaluation represented various combinations of estimating M or q as free parameters with different amounts of uncertainty in the parameter estimates (Wilderbuer et al. 2010). The results are detailed in those assessments and are not repeated here except for the following observations. Modeling survey catchability as a nonlinear function of bottom water temperature returns q estimates > 1.0 for years when the bottom temperature is anomalously warm (greater than the mean temperature) and less than 1.0 when below the temperature mean. These values are consistent with our hypothesis that more fish are available to the survey in warm years relative to cooler years due to the timing of the annual spawning migration to nearshore areas that occurs sooner in warm years. Experiments examining the bridle efficiency of the Bering Sea survey trawl indicate that yellowfin sole are herded into the trawl path from an area between the wing tips of the net and the point where the bridles contact the seafloor (Somerton and Munro 2001). The herding experiments suggest that the survey trawl catchability is greater than 1.0. The likelihood profile of q from the model indicated a small variance with a narrow range of likely values with a low probability of q being equal to the value of 1.0 in a past assessment (Wilderbuer and Nichol 2003). A model that allows M to be estimated as a free parameter for males with females fixed at 0.12 provided a better fit to the sex ratio estimated from the annual trawl survey age compositions than did the base model (both sexes fixed at M = 0.12). However, since the population sex ratio annually observed at the time of the survey is a function of the timing of the annual spawning in adjacent inshore areas, it is questionable that providing the best fit to these observations is really fitting the population sex ratio better. Thus, the model configuration which utilizes the relationship between annual seafloor temperature and survey catchability with M fixed at 0.12 for both sexes (Model 14_1) is the preferred model used to base the assessment of the condition of the Bering Sea yellowfin sole resource for the 2018 fishing season.

Time Series Results Before presenting the preferred model results, a brief consideration of the inputs and changes to the assessment methodology relative to last year (Model 14_1) is given. Primary updates for Model 14_1 were the 2017 catch, the fishery and survey age compositions from 2016 and the 2017 survey biomass (3% lower than 2016) and standard error estimates. The fishery and survey weights-at-age were also changed in a small amount to include the latest year of data and the spawner-recruit data was increased by 2 years to include the 2011 and 2012 year-class recruitment estimates. In their totality, these changes produced a Model 14_1 FABC estimate that was 5% lower than 2016 and a FOFL that was 4% lower. This increase was mostly due to refitting the spawner-recruit curve with the averaged fishery weight-at- age data which had the effect of moving the curve and BMSY to the right (higher Bmsy, lower Fmsy for Tier 1 stocks).

Comparison of spawner-recruit curves between

3000 2016 and 2017

2500

2000

1500

1000

500 recruitment (millions) 0 0 200 400 600 800 1000 1200 female spawning biomass (1,000s t)

2016 2017

The 2017 overall estimate (1982 – 2017) of trawl survey catchability decreased from 0.95 to 0.9. This resulted in higher model estimates of population numbers at age and biomass for the time-series back to the mid-1960s relative to last year’s assessment and increased the estimated level of female spawning biomass. The model results indicate the stock has been in a slowly declining condition since the mid- 1980s. The estimates of total biomass and ABC are higher than those used to manage the stock in 2017. Seven of the past 11 years have had negative bottom temperature anomalies in the Bering Sea but the last four have been above the mean. The temperature-dependent q adjustment for 2017 was 0.92. Fishing Mortality and Selectivity The assessment model estimates of the annual fishing mortality in terms of age-specific annual F and on fully selected ages are given in Tables 4.14 and 4.15, respectively. The full-selection F has averaged 0.08 over the period of 1978-2017 with a maximum of 0.12 in 1978 and a minimum of 0.04 in 2001. Selectivities estimated by the model (Table 4.16, Fig. 4.15) indicate that both sexes of yellowfin sole are 50% selected by the fishery at about age 9 and nearly fully selected by age 13, with annual varability. Abundance Trend The model estimates q at an average value of 0.9 for the period 1982-2017 which results in the model estimate of the 2016 age 2+ total biomass at 2,878,100 t (Table 4.17). Model results indicate that yellowfin sole total biomass (age 2+) was at low levels during most of the 1960s and early 1970s (700,000-1,000,000 t) after a period of high exploitation (Table 4.17, Fig. 4.16, center left panel).

Sustained above average recruitment from 1967-76 combined with light exploitation resulted in a biomass increase to a peak of 3.5 million t by 1985. The population biomass has since been in a slow decline as the strong 1981 and 1983 year-classes have passed through the population, with only the 1991, 1995 and 2003 year-classes at levels observed during the 1970s. The present biomass is estimated at 82% of the peak 1985 level. The female spawning biomass has also declined since the peak in 1994, with a 2017 estimate of 884,800 t (22% decline). The spawning biomass has been in a gradual decline for the past 22 years and is 30% above the B40% level and 1.9 times the BMSY level (Fig. 4.16). The model estimate of yellowfin sole population numbers at age for all years is shown in Table 4.18 and the resulting fit to the observed fishery and survey age compositions input into the model are shown in the Figure 4.17. The fit to the trawl survey biomass estimates are shown in Figure 4.16. Allowing q to be correlated with annual bottom temperature provides a better fit to the bottom trawl survey estimates than using a q fixed at the average value (Fig. 4.18). Table 4.19 lists the numbers of female spawners estimated by the model for all ages and years. The estimated average age of yellowfin sole in the population is 6.7 years for males and females. Both the trawl survey and the stock assessment model indicate that the yellowfin sole resource increased during the 1970s and early 1980s to a peak level during the mid-1980s. The yellowfin sole population biomass slowly decreased over the 22 years since the mid-1990s as the majority of year-classes during those years were below average strength. Average to above average recruitment from 2006 to 2009 is expected to maintain the abundance of yellowfin sole at a level above BMSY in the near future. The stock assessment projection model indicates a mildly decreasing trend in female spawning biomass through 2024 if the fishing mortality rate continues at the same level as the average of the past 5 years (Fig. 4.22). Recruitment Trends The primary reason for the sustained increase in abundance of yellowfin sole during the 1970s and early 1980s was the recruitment of a series of stronger than average year classes spawned in 1967-76 (Figure 4.19 and Table 4.20). The 1981 year class was the strongest observed (and estimated) during the 47 year period analyzed and the 1983 year class was also very strong. Survey age composition estimates and the assessment model also estimate that the 1987 and 1988 year classes were average and the 1991 and 1995 year classes were above average. With the exception of these 4 year classes, recruitment from 15 of the following 19 years estimated from 1984-2005 (since the strong 1983 year-class) were below the 48 year average, which caused the population to gradually decline. The 2003 year-class has now been observed multiple times in the age compositions and is clearly a strong year class, similar to some of the strong recruitment mentioned above and are contributing to the reservoir of spawning fish in the current population. In addition, recruitment from 2006-2009 appear also to be average to above average. Historical Exploitation Rates Based on results from the stock assessment model, annual average exploitation rates of yellowfin sole since 1977 ranged from 3 to 7% of the total biomass, and have averaged 4% (Table 4.15). Posterior distributions of selected parameters from the preferred stock assessment model used in the assessment are shown in Figure 4.20. The values and standard deviations of some selected model parameters are listed in Table 4.21. Retrospective analysis A within-model retrospective analysis is also included for the recommended assessment model (Model 14_1) where retrospective female spawning biomass is calculated by working backwards in time dropping data one year at a time and then comparing the “peeled” estimate to the reference stock assessment model used in the assessment (Fig. 4.21). The resulting pattern from the current assessment model was less than desirable. Peculiar to the yellowfin sole assessment, in comparison to the northern rock sole and Alaska plaice assessments (that have nice patterns), is the large amount of variability in the annual survey biomass

assessments for this stock due to the temperature-influenced availability to the survey. This large variability in the annual estimates can contribute to undesirable patterns since the earlier years are not fitting the same highly variable information as the current year. Exploratory model runs were made to examine the influence of fitting the survey biomass on the retrospective patterns. This was accomplished by making model runs that increased the survey biomass standard error by 10%, 20% and 30%, and also runs that attempted to decrease the influence of fitting the survey age composition by decreasing the effective n, and also a run with a fixed q (no bottom temp modeling). The models are listed below and are evaluated using Mohn’s test statistic. Model Description Mohn’s test statistic Current stock assessment model (Model 2) -0.193 Model 14_1 with survey standard error increased by 10% -0.239 Model 14_1 with survey standard error increased by 20% -0.211 Model 14_1 with survey standard error increased by 30% -0.219 Down-weighted survey age comps, base st. dev values -0.207

Up-weighted survey age comps (500) and down-weighted survey SE -0.238 (increased st. dev value by 30%)

survey q fixed at 1.05 for all runs -0.186

A small gain was made by fixing q at 1.05 (M = 0.12) whereas all the other runs had similar results, increasing the test statistic over the base value (lower is better). The Plan Team suggested examining the effect that q and M have on the retrospective patterns. Responding to this request, model runs were made varying M from 0.9 to 0.14 and q from 0.8 to 1.2 (fixed M and q, no temperature modeling). Decreasing values of q and M gave better retrospective patterns and lower Mohn’s test statistic. Catchability 0.8 0.9 1 1.1 1.2 0.09 0.019 0.003 0.028 0.0511 0.076 0.1 0.013 0.036 0.059 0.084 0.107 Natural mortality 0.11 0.043 0.066 0.087 0.11 0.131 0.12 0.07 0.105 0.113 0.135 0.155 0.13 0.051 0.114 0.135 0.156 0.177 0.14 0.114 0.135 0.153 0.177 0.2 Hotter colors correspond to lower test statistic values. Figure below is an example of retrospective pattern with low M and q.

Estimated female spawning biomass M=0.09,q=1.0,rho=-0.028 1200 1000 800 600 400 200 0 1950 1960 1970 1980 1990 2000 2010 2020

2016 2015 2014 2013 2012 2011 2010 2009 2008 2007

Harvest Recommendations The SSC has determined that yellowfin sole qualify as a Tier 1 stock and therefore the 2018 ABC is calculated using Tier 1 methodology. The Tier 1 harvest level is calculated as the product of the harmonic mean of FMSY and the geometric mean of the 2018 biomass estimate, as follows:

∧ cv2 ln B − 2 ∧ B gm = e , where Bgm is the geometric mean of the 2018 biomass estimate, B is the point estimate of the 2018 biomass from the stock assessment model and cv2 is the coefficient of variation of the point estimate (a proxy for sigma); and

∧ 2 − ln sd ln F msy − − ∧ 2 Fhar = e , where F har is the harmonic mean, F msy is the peak mode of the FMSY 2 distribution and sd is the square of the standard deviation of the FMSY distribution. In 2006 the SSC selected the 1978-2001 data set for the Tier 1 harvest recommendation. Using this approach again for the 2018 harvest (now the 1978-2012 time-series) recommendation (Model 14_1 in Table 4.13), the FABC = Fharmonic mean = 0.109. The estimate of age 6+ total biomass for 2018 is 2,553,100 t. The calculations outlined above give a Tier 1 ABC harvest recommendation of 277,500 t and an OFL of 306,700 t for 2018. This results in an 11% (29,250 t) buffer between ABC and OFL. The ABC value is 6% higher than last year, primarily due to changes to the spawner-recruit curve from the fishery weight- at-age modeling and a lower catchability estimate. The stock assessment analysis must also consider harvest limits, usually described as overfishing fishing mortality levels with corresponding yield amounts. Amendment 56 to the BSAI FMP sets the Tier 1 harvest limit at the FMSY fishing mortality value. The overfishing fishing mortality values, ABC fishing mortality values and their corresponding yields are given as follows: Harvest level F value 2018 Yield

Tier 1 FOFL = FMSY 0.12 306,700 t

Tier 1 FABC = Fharmonic mean 0.109 277,500 t

Status Determination A standard set of projections is required for each stock managed under Tiers 1, 2, or 3 of Amendment 56. This set of projections encompasses seven harvest scenarios designed to satisfy the requirements of Amendment 56, the National Environmental Policy Act, and the Magnuson-Stevens Fishery Conservation and Management Act (MSFCMA). For each scenario, the projections begin with the vector of 2017 numbers at age estimated in the assessment. This vector is then projected forward to the beginning of 2018 using the schedules of natural mortality and selectivity described in the assessment and the best available estimate of total (year-end) catch for 2017. In each subsequent year, the fishing mortality rate is prescribed on the basis of the spawning biomass in that year and the respective harvest scenario. In each year, recruitment is drawn from an inverse Gaussian distribution whose parameters consist of maximum likelihood estimates determined from recruitments estimated in the assessment. Spawning biomass is computed in each year based on the time of peak spawning and the maturity and weight schedules described in the assessment. Total catch is assumed to equal the catch associated with the respective harvest scenario in all years. This projection scheme is run 1000 times to obtain distributions of possible future stock sizes, fishing mortality rates, and catches. Five of the seven standard scenarios will be used in an Environmental Assessment prepared in conjunction with the final SAFE. These five scenarios, which are designed to provide a range of harvest alternatives that are likely to bracket the final TAC for 2018, are as follows (“max FABC” refers to the maximum permissible value of FABC under Amendment 56):

Scenario 1: In all future years, F is set equal to max FABC. (Rationale: Historically, TAC has been constrained by ABC, so this scenario provides a likely upper limit on future TACs.)

Scenario 2: In all future years, F is set equal to a constant fraction of max FABC, where this fraction is equal to the ratio of the FABC value for 2018 recommended in the assessment to the max FABC for 2018. (Rationale: When FABC is set at a value below max FABC, it is often set at the value recommended in the stock assessment.) Scenario 3: In all future years, F is set equal to the 2013-2017 average F. (Rationale: For some stocks, TAC can be well below ABC, and recent average F may provide a better indicator of FTAC than FABC.)

Scenario 4: In all future years, the upper bound on FABC is set at F60%. (Rationale: This scenario provides a likely lower bound on FABC that still allows future harvest rates to be adjusted downward when stocks fall below reference levels.) 0Scenario 5: In all future years, F is set equal to zero. (Rationale: In extreme cases, TAC may be set at a level close to zero.) Two other scenarios are needed to satisfy the MSFCMA’s requirement to determine whether a stock is currently in an overfished condition or is approaching an overfished condition. These two scenarios are as follow (for Tier 3 stocks, the MSY level is defined as B35%):

Scenario 6: In all future years, F is set equal to FOFL. (Rationale: This scenario determines whether a stock is overfished. If the stock is expected to be above its MSY level in 2016 and above its MSY level in 2029 under this scenario, then the stock is not overfished.)

Scenario 7: In 2018 and 2019, F is set equal to max FABC, and in all subsequent years, F is set equal to FOFL. (Rationale: This scenario determines whether a stock is approaching an overfished condition. If the stock is expected to be above its MSY level in 2030 under this scenario, then the stock is not approaching an overfished condition.) Simulation results shown in Table 4.22 indicate that yellowfin sole are not currently overfished and are not approaching an overfished condition. The projection of yellowfin sole female spawning biomass

through 2030 is shown in Figure 4.22 and a phase plane figure of the estimated time-series of yellowfin sole female spawning biomass relative to the harvest control rule is shown in Figure 4.23. Scenario Projections and Two-Year Ahead Overfishing Level In addition to the seven standard harvest scenarios, Amendments 48/48 to the BSAI and GOA Groundfish Fishery Management Plans require projections of the likely OFL two years into the future. The 2016 numbers at age from the stock assessment model are projected to 2017 given the 2016 catch and then a 2017 catch of 150,000 t is applied to the projected 2017 population biomass to obtain the 2018 OFL.

Tier 1 Projection Geometric mean 6+ total Year Catch SSB biomass ABC OFL 2018 150,000 895,000 2,553,100 277,500 306,700 2019 150,000 890,000 2,460,700 267,400 295,600

Ecosystem Considerations

Ecosystem Effects on the stock 1) Prey availability/abundance trends Yellowfin sole diet by life stage varies as follows: Larvae consume plankton and algae, early juveniles consume zooplankton, late juvenile stage and adults prey includes bivalves, , amphipods, mollusks, euphausids, shrimps, brittle stars, and miscellaneous crustaceans. Information is not available to assess the abundance trends of the benthic infauna of the Bering Sea shelf. The original description of infaunal distribution and abundance by Haflinger (1981) resulted from sampling conducted in 1975 and 1976 and has not been re-sampled since. The large populations of flatfish which have occupied the middle shelf of the Bering Sea over the past twenty-five years for summertime feeding do not appear food-limited. These populations have fluctuated due to the variability in recruitment success which suggests that the primary infaunal food source has been at an adequate level to sustain the yellowfin sole resource.

% weight of prey in yellowfin sole diet from 122 stomachs collected in 2000 unident mis c snail my s ids polychaetes 19% brittle stars clams 14% Hermit crab miscellaneous worms non-pelagic shrimp 13% 10% benthic amph

2) Predator population trends As juveniles, it is well-documented from studies in other parts of the world that flatfish are prey for shrimp species in near shore areas. This has not been reported for Bering Sea yellowfn sole due to a lack of juvenile sampling and collections in near shore areas, but is thought to occur. As late juveniles they have been found in stomachs of Pacific cod and Pacific ; mostly small yellowfin sole ranging from 7 to 25 cm standard length.. Past, present and projected future population trends of these predator species can be found in their respective SAFE chapters in this volume and also from Annual reports compiled by the International

Pacific Halibut Commission. Encounters between yellowfin sole and their predators may be limited since their distributions do not completely overlap in space and time. 3) Changes in habitat quality Changes in the physical environment which may affect yellowfin sole distribution patterns, recruitment success and migration timing patterns are catalogued in the Ecosystem Considerations Report of this SAFE report. Habitat quality may be enhanced during years of favorable cross-shelf advection (juvenile survival) and warmer bottom water temperatures with reduced ice cover (higher metabolism with more active feeding).

Fishery Effects on the ecosystem 1) The yellowfin sole target fishery contribution to the total bycatch of other target species is shown for 1992-2016 in Table 4.23. The catch of non-target species from 2003-2016 is shown in Table 4.24. The yellowfin sole target fishery contribution to the total bycatch of prohibited species is shown for 2014 and 2015 in Table 13 of the Economic SAFE (Appendix C) and is summarized for 2015 as follows: Prohibited species Yellowfin sole fishery % of total bycatch Halibut mortality 30 Herring 2 Red King crab 5 C. bairdi 25.5 Other Tanner crab 78.2 Salmon <1

2) Relative to the predator needs in space and time, the yellowfin sole target fishery has a low selectivity for fish 7-25 cm and therefore has minimal overlap with removals from predation. 3) The target fishery is not perceived to have an effect on the amount of large size target fish in the population due to its history of light to moderate exploitation (6%) over the past 30 years. Population age composition data indicate a large 20+ age group. 4) Yellowfin sole fishery discards are presented in the Catch History section. 5) It is unknown what effect the fishery has had on yellowfin sole maturity-at-age and fecundity, but based on two maturity studies conducted 20 years apart, it is expected to be minimal. 6) Analysis of the benthic disturbance from the yellowfin sole fishery is available in the Preliminary draft of the Essential Fish Habitat Environmental Impact Statement.

Ecosystem effects on yellowfin sole Indicator Observation Interpretation Evaluation Prey availability or abundance trends Benthic infauna Stomach contents Stable, data limited Unknown

Predator population trends

Possible increases to Fish (Pacific cod, halibut, Stable yellowfin sole skates) mortality Changes in habitat quality No concern Temperature regime Cold years yellowfin sole catchability Likely to affect (dealt with in and herding may decrease, timing of surveyed stock model) migration may be prolonged Winter-spring Affects pre-recruit survival Probably a number of Causes natural environmental conditions factors variability

Yellowfin sole effects on ecosystem Indicator Observation Interpretation Evaluation Fishery contribution to bycatch Minor contribution to Prohibited species Stable, heavily monitored mortality No concern Forage (including herring, Bycatch levels small Atka mackerel, cod, and relative to forage pollock) Stable, heavily monitored biomass No concern Bycatch levels small HAPC biota Low bycatch levels of (spp) relative to HAPC biota No concern Marine mammals and birds Very minor direct-take Safe No concern Sensitive non-target species Likely minor impact Data limited, likely to No concern be safe Fishery concentration in space Low exploitation rate No concern and time Little detrimental effect

Fishery effects on amount of Low exploitation rate Natural fluctuation No concern large size target fish Fishery contribution to discards Improving, but data Stable trend Possible concern and offal production limited Fishery effects on age-at- Unknown NA Possible concern maturity and fecundity

Data Gaps and Research Priorities Isolation by distance genetic study to define stock structure in the planning stage. NPRB proposal to collect maturity in the northern Bering Sea for comparison with recent SE Bering Sea shelf samples.

References Alaska Fisheries Science Center. 2016. Wholesale market profiles for Alaska groundfish and crab fisheries. 134 p. Alaska Fish. Sci. Cent., NOAA, Natl. Mar. Fish. Serv. 7600 Sand Point Way NE. Seattle, WA. Bakkala, R. G. and V. Wespestad. 1984. Yellowfin sole. In R. G. Bakkala and L. resources of the eastern Bering Sea and Aleutian Islands region in 1983, p. 37-60. U.S. Dep. Commer., NOAA Tech. Memo. NMFS F/NWC-53. Bakkala, R. G., V. Wespestad, and L. Low. 1982. The yellowfin sole (Limanda aspera) resource of the eastern Bering Sea--its current and future potential for commercial fisheries. U.S. Dep. Commer., NOAA Tech. Memo. NMFS F/NWC-33, 43p. Bakkala, R. G., and T. K. Wilderbuer. 1990. Yellowfin sole. In Stock Assessment and Fishery Evaluation Document for Groundfish Resources in the Bering Sea/Aleutian Islands Region as Projected for 1990, p. 60-78. North Pacific Fishery Management Council, P. O. Box 103136, Anchorage, Ak 99510. Clark, W. G., Hare, S. R., Parms, A. M., Sullivan, P, J., Trumble, R. J. 1999. Decadal changes in growth and recruitment of (Hipplglossus stenolepis). Can. J. fish. Aquat. Sci. 56, 242- 252. Fournier, D. A., H.G. Skaug, J. Ancheta, J. Ianelli, A. Magnusson, M. N. Maunder, A. Nielsen, and J. Sibert. 2012. AD Model Builder: using automatic differentiation for statistical inference of highly parameterized complex nonlinear models. Optim. Methods Softw. 27:233-239. Fournier, D. A. and C.P. Archibald. 1982. A general theory for analyzing catch-at-age data. Can. J. Fish Aquat. Sci. 39:1195-1207. Greiwank, A. and G. F. Corliss (eds) 1991. Automatic differentiation of algorithms: theory, implementation and application. Proceedings of the SIAM Workshop on the Automatic Differentiation of Algorithms, held Jan. 6-8, Breckenridge, CO. Soc. Indust. And Applied Mathematics, Philadelphia. Haflinger, K. 1981. A survey of benthic infaunal communities of the Southeastern Bering Sea shelf. In Hood and Calder (editors) The Eastern Bering Sea Shelf: Oceanography and Resources, Vol. 2. P. 1091-1104. Office Mar. Pol. Assess., NOAA. Univ. Wash. Press, Seattle, Wa 98105. Ianelli, J. N. and D. A. Fournier. 1998. Alternative age-structured analyses of the NRC simulated stock assessment data. In Restrepo, V. R. [ed.] Analyses of simulated data sets in support of the NRC study on stock assessment methods. NOAA Tech. Memo. NMFS-F/SPO-30. 96 p. Kastelle, C., T. Helser, S. Wischniowski, T. Loher, B. Geotz and L. Kautzi. 2016. Incorporation of bomb-produced 14C into fish otoliths: A novel approach for evaluating age validation and bias with an application to yellowfin sole and northern rockfish. Ecological modeling 320 (2016) 79- 91. Low, L. and R.E. Narita. 1990. Condition of groundfish resources in the Bering Sea-Aleutian Islands region as assessed in 1988. U.S. Dep. Commer., NOAA Tech. Memo. NMFS-F/NWC-178, 224 p. Matta, M. E., B. A. Black and T. K. Wilderbuer. 2010. Climate-driven synchrony in otolith growth- increment chronologies for three Bering Sea flatfish species. MEPS, Vol. 413:137-145, 2010. Nichol, D. R . 1995. Spawning and maturation of female yellowfin sole in the eastern Bering Sea. In Proceedings of the international flatfish symposium, October 1994, Anchorage, Alaska, p. 35-50. Univ. Alaska, Alaska Sea Grant Rep. 95-04.

Nichol, D.R. 1998. Annual and between sex variability of yellowfin sole, Pleuronectes asper, spring- summer distributions in the eastern Bering Sea. Fish. Bull., U.S. 96: 547-561. Ricker, W. E. 1958. Handbook of computations for biological statistics of fish populations. Bull. Fish. Res. Bd. Can., (119) 300 p. Rose, C. S., J. R. Gauvin and C. F. Hammond. 2010. Effective herding of flatfish by cables with minimal seafloor contact. Fishery Bulletin 108(2):136-144. Somerton, D. A. and P. Munro. 2001. Bridle efficiency of a survey trawl for flatfish. Fish. Bull. 99:641- 652 (2001). TenBrink, T. T. and T. K. Wilderbuer. 2015. Updated maturity estimates for () in the eastern Bering Sea, with notes on histology and implications to fisheries management. Coastal and Marine Fisheries: Dynamics, Management and Ecosystem Science. O:1-9. 2015. DOI: 10.1080/19425120.2015.1091411. Wakabayashi, K. 1989. Studies on the fishery biology of yellowfin sole in the eastern Bering Sea. [In Jpn., Engl. Summ.] Bull. Far Seas Fish. Res. Lab. 26:21-152. Wakabayashi, K., R. Bakkala, and L. Low. 1977. Status of the yellowfin sole resource in the eastern Bering Sea through 1976. Unpubl. manuscr., 45p. Northwest and Alaska Fish. Cent., Natl. Mar. Fish. Serv., NOAA, 7600 Sand Point Way N.E., Bin C 15700, Seattle, Wa 98115. Walters, G. E. and T. K. Wilderbuer. 2000. Decreasing length at age in a rapidly expanding population of northern rock sole in the eastern Bering Sea and its effect on management advice. Journal of Sea Research 44(2000)17-26. Wilderbuer, T. K. 1992. Yellowfin sole. In Stock Assessment and Fishery Evaluation Document for Groundfish Resources in the Bering Sea/Aleutian Islands Region as Projected for 1993, chapter 3. North Pacific Fishery Management Council, P. O. Box 103136, Anchorage, Ak 99510. Wilderbuer, T. K. 1993. Yellowfin sole. In Stock Assessment and Fishery Evaluation Document for Groundfish Resources in the Bering Sea/Aleutian Islands Region as Projected for 1994, chapter 3. North Pacific Fishery Management Council, P. O. Box 103136, Anchorage, Ak 99510. Wilderbuer, T. K. and D. Nichol. 2001. Yellowfin sole. In Stock Assessment and Fishery Evaluation Document for Groundfish Resources in the Bering Sea/Aleutian Islands Region as Projected for 2004, chapter 4. North Pacific Fishery Management Council, P. O. Box 103136, Anchorage, Ak 99510. Wilderbuer, T. K. and D. Nichol. 2003. Yellowfin sole. In Stock Assessment and Fishery Evaluation Document for Groundfish Resources in the Bering Sea/Aleutian Islands Region as Projected for 2004, chapter 4. North Pacific Fishery Management Council, P. O. Box 103136, Anchorage, Ak 99510. Wilderbuer, T. K. D. G. Nichol, and J. Ianelli. 2010. Yellowfin sole. In Stock Assessment and Fishery Evaluation Document for Groundfish Resources in the Bering Sea/Aleutian Islands Region as Projected for 2011, chapter 4. North Pacific Fishery Management Council, P. O. Box 103136, Anchorage, Ak 99510. Wilderbuer, T.K., G.E. Walters, and R.G. Bakkala 1992. Yellowfin sole, Pleuronectes asper, of the eastern Bering Sea: biological characteristics, history of exploitation, and management. Mar Fish. Rev. 54(4):1-18.

Tables

Table 4.1--Catch (t) of yellowfin sole 1964-2017. Catch for 2017 is an estimate through the end of 2017. Domestic Year Foreign JVP DAP Total 1964 111,777 111,777 1965 53,810 53,810 1966 102,353 102,353 1967 162,228 162,228 1968 84,189 84,189 1969 167,134 167,134 1970 133,079 133,079 1971 160,399 160,399 1972 47,856 47,856 1973 78,240 78,240 1974 42,235 42,235 1975 64,690 64,690 1976 56,221 56,221 1977 58,373 58,373 1978 138,433 138,433 1979 99,019 99,019 1980 77,768 9,623 87,391 1981 81,255 16,046 97,301 1982 78,331 17,381 95,712 1983 85,874 22,511 108,385 1984 126,762 32,764 159,526 1985 100,706 126,401 227,107 1986 57,197 151,400 208,597 1987 1,811 179,613 4 181,428 1988 213,323 9,833 223,156 1989 151,501 1,664 153,165 1990 69,677 14,293 83,970 1991 115,842 115,842 1992 149,569 149,569 1993 106,101 106,101 1994 144,544 144,544 1995 124,740 124,740 1996 129,659 129,659 1997 181,389 181,389 1998 101,201 101,201 1999 67,320 67,320 2000 83,850 83,850 2001 63,395 63,395 2002 73,000 73,000 2003 74,418 74,418 2004 69,046 69,046 2005 94,383 94,383 2006 99,068 99,068 2007 121,029 121,029 2008 148,894 148,894 2009 107,528 107,528 2010 118,624 118,624 2011 151,164 151,164 2012 147,183 147,183 2013 164,944 164,944 2014 156,778 156,778 2015 126,933 126,933 2016 135,353 135,353 2017 143,100 143,100

Table 4.2. Estimates of retained and discarded (t) yellowfin sole caught in Bering Sea fisheries. Year Retained Discarded 1987 3 1 1988 7,559 2,274 1989 1,279 385 1990 10,093 4,200 1991 89,054 26,788 1992 103,989 45,580 1993 76,798 26,838 1994 107,629 36,948 1995 96,718 28,022 1996 101,324 28,334 1997 149,570 31,818 1998 80,365 20,836 1999 55,202 12,118 2000 69,788 14,062 2001 54,759 8,635 2002 62,050 10,950 2003 63,732 10,686 2004 57,378 11,668 2005 85,321 9,062 2006 90,570 8,498 2007 109,084 11,945 2008 141,253 7,659 2009 92,488 5,733 2010 113,244 5,380 2011 146,419 4,745 2012 143,737 3,446 2013 158,781 6,163 2014 152,164 4,614 2015 123,065 3,871 2016 131,205 4,148

Table 4.3. Discarded and retained catch of non-CDQ yellowfin sole, by fishery, in 2016. Source: AKFIN. Trip Target Name Discarded Retained Atka Mackerel <1 <1 Pollock - bottom 4 297 Pacific Cod 1,636 315 Alaska Plaice - BSAI 6 260 Other Flatfish - BSAI <1 Halibut Rockfish <1 <1 Flathead Sole 92 2,403 Kamchatka Flounder - BSAI <1 <1 Pollock - midwater 172 415 Rock Sole - BSAI 598 21,646 Sablefish Greenland - BSAI 0 Arrowtooth <1 <1 Yellowfin Sole - BSAI 1,637 105,868

Table 4.4. Yellowfin sole fishery catch-at-age (proportions), 1975-2016. males 7 8 9 10 11 12 13 14 15 16 17+ 1975 0.09 0.24 0.12 0.02 0.01 0.01 0.02 0.00 0.00 0.00 0.00 1976 0.05 0.04 0.14 0.11 0.04 0.02 0.02 0.00 0.01 0.00 0.00 1977 0.03 0.08 0.07 0.12 0.09 0.04 0.01 0.00 0.00 0.00 0.00 1978 0.05 0.09 0.07 0.07 0.07 0.03 0.02 0.01 0.00 0.00 0.00 1979 0.03 0.06 0.11 0.07 0.06 0.04 0.02 0.00 0.00 0.00 0.00 1980 0.04 0.02 0.03 0.05 0.05 0.05 0.03 0.01 0.01 0.01 0.01 1981 0.04 0.04 0.03 0.05 0.07 0.06 0.04 0.02 0.01 0.00 0.00 1982 0.04 0.06 0.05 0.05 0.07 0.07 0.04 0.02 0.01 0.00 0.00 1983 0.06 0.03 0.06 0.05 0.04 0.06 0.05 0.03 0.02 0.01 0.01 1984 0.01 0.06 0.04 0.08 0.04 0.05 0.05 0.10 0.04 0.02 0.01 1985 0.02 0.03 0.06 0.06 0.07 0.06 0.07 0.06 0.03 0.02 0.02 1986 0.03 0.02 0.05 0.06 0.04 0.04 0.04 0.02 0.04 0.04 0.05 1987 0.02 0.05 0.04 0.05 0.04 0.05 0.06 0.04 0.02 0.03 0.13 1988 0.03 0.04 0.09 0.02 0.04 0.04 0.02 0.05 0.04 0.01 0.08 1989 0.00 0.04 0.04 0.06 0.02 0.02 0.04 0.03 0.03 0.03 0.16 1990 0.05 0.01 0.18 0.02 0.05 0.02 0.03 0.04 0.00 0.04 0.07 1991 0.01 0.09 0.01 0.19 0.03 0.06 0.01 0.01 0.02 0.02 0.07 1992 0.01 0.03 0.10 0.03 0.14 0.02 0.02 0.02 0.01 0.01 0.04 1993 0.02 0.01 0.01 0.08 0.01 0.10 0.02 0.02 0.01 0.02 0.09 1994 0.02 0.04 0.03 0.02 0.11 0.01 0.09 0.01 0.03 0.01 0.05 1995 0.03 0.06 0.03 0.01 0.02 0.10 0.00 0.10 0.01 0.01 0.05 1996 0.02 0.06 0.04 0.02 0.01 0.03 0.10 0.02 0.07 0.01 0.06 1997 0.02 0.02 0.05 0.04 0.03 0.04 0.02 0.10 0.02 0.05 0.09 1998 0.02 0.02 0.02 0.05 0.04 0.03 0.01 0.02 0.03 0.01 0.12 1999 0.00 0.02 0.01 0.02 0.04 0.05 0.03 0.02 0.03 0.04 0.11 2000 0.00 0.02 0.05 0.01 0.02 0.05 0.03 0.03 0.02 0.05 0.13 2001 0.01 0.02 0.01 0.03 0.03 0.01 0.02 0.03 0.03 0.02 0.16 2002 0.00 0.02 0.03 0.04 0.09 0.03 0.02 0.05 0.01 0.01 0.14 2003 0.01 0.08 0.04 0.03 0.02 0.04 0.02 0.02 0.03 0.02 0.15 2004 0.01 0.02 0.09 0.02 0.02 0.02 0.03 0.01 0.01 0.02 0.19 2005 0.01 0.04 0.02 0.08 0.02 0.02 0.03 0.04 0.02 0.01 0.14 2006 0.06 0.05 0.03 0.05 0.06 0.02 0.01 0.02 0.03 0.01 0.09 2007 0.02 0.06 0.03 0.03 0.05 0.06 0.02 0.02 0.03 0.02 0.12 2008 0.02 0.03 0.06 0.02 0.03 0.02 0.07 0.01 0.02 0.02 0.11 2009 0.01 0.04 0.03 0.05 0.03 0.01 0.02 0.04 0.02 0.02 0.13 2010 0.06 0.03 0.06 0.02 0.05 0.04 0.02 0.01 0.02 0.01 0.10 2011 0.02 0.07 0.03 0.03 0.03 0.04 0.01 0.01 0.01 0.03 0.14 2012 0.02 0.04 0.08 0.04 0.03 0.03 0.04 0.04 0.01 0.02 0.16 2013 0.02 0.00 0.03 0.08 0.05 0.06 0.04 0.04 0.03 0.01 0.09 2014 0.02 0.04 0.03 0.04 0.06 0.02 0.04 0.04 0.04 0.01 0.13 2015 0.01 0.03 0.04 0.02 0.02 0.05 0.02 0.05 0.02 0.04 0.16 2016 0.02 0.03 0.03 0.05 0.04 0.02 0.05 0.03 0.02 0.01 0.17

Table 4.4- continued. females 7 8 9 10 11 12 13 14 15 16 17+ 1975 0.05 0.14 0.09 0.05 0.02 0.02 0.02 0.00 0.01 0.00 0.00 1976 0.04 0.07 0.17 0.10 0.07 0.01 0.01 0.00 0.01 0.00 0.00 1977 0.07 0.16 0.11 0.02 0.01 0.01 0.00 0.00 0.00 0.00 0.00 1978 0.05 0.13 0.12 0.09 0.09 0.03 0.01 0.01 0.00 0.00 0.00 1979 0.03 0.07 0.12 0.12 0.08 0.06 0.03 0.01 0.01 0.00 0.00 1980 0.06 0.04 0.06 0.11 0.10 0.07 0.07 0.04 0.02 0.01 0.03 1981 0.06 0.06 0.03 0.05 0.09 0.11 0.07 0.05 0.02 0.01 0.01 1982 0.03 0.07 0.06 0.05 0.09 0.09 0.05 0.03 0.02 0.01 0.00 1983 0.07 0.05 0.08 0.04 0.05 0.07 0.06 0.05 0.03 0.02 0.01 1984 0.03 0.04 0.05 0.09 0.04 0.06 0.05 0.06 0.03 0.01 0.02 1985 0.02 0.02 0.06 0.05 0.07 0.06 0.05 0.06 0.05 0.01 0.01 1986 0.03 0.03 0.04 0.09 0.07 0.06 0.04 0.03 0.04 0.03 0.06 1987 0.01 0.03 0.02 0.04 0.05 0.05 0.06 0.05 0.03 0.03 0.09 1988 0.02 0.03 0.07 0.02 0.04 0.05 0.04 0.06 0.05 0.02 0.12 1989 0.00 0.04 0.05 0.05 0.03 0.03 0.05 0.02 0.05 0.05 0.15 1990 0.02 0.01 0.13 0.03 0.06 0.03 0.02 0.01 0.01 0.08 0.09 1991 0.01 0.07 0.01 0.11 0.04 0.04 0.01 0.03 0.04 0.02 0.09 1992 0.01 0.02 0.09 0.02 0.14 0.04 0.04 0.01 0.03 0.02 0.12 1993 0.02 0.01 0.02 0.09 0.01 0.12 0.03 0.03 0.02 0.03 0.18 1994 0.02 0.03 0.03 0.03 0.16 0.00 0.10 0.01 0.04 0.02 0.13 1995 0.04 0.06 0.02 0.01 0.02 0.10 0.00 0.16 0.01 0.03 0.12 1996 0.01 0.04 0.06 0.02 0.03 0.03 0.07 0.01 0.11 0.01 0.11 1997 0.02 0.02 0.06 0.03 0.02 0.03 0.03 0.10 0.01 0.06 0.10 1998 0.02 0.03 0.08 0.04 0.02 0.04 0.04 0.12 0.01 0.07 0.13 1999 0.01 0.02 0.03 0.02 0.08 0.05 0.03 0.04 0.04 0.07 0.23 2000 0.00 0.01 0.05 0.03 0.03 0.07 0.08 0.05 0.02 0.04 0.22 2001 0.01 0.02 0.05 0.08 0.05 0.04 0.07 0.05 0.04 0.02 0.16 2002 0.01 0.02 0.03 0.04 0.06 0.04 0.03 0.04 0.05 0.02 0.21 2003 0.00 0.05 0.04 0.03 0.04 0.08 0.03 0.02 0.02 0.03 0.19 2004 0.01 0.01 0.10 0.05 0.03 0.02 0.05 0.02 0.01 0.05 0.19 2005 0.02 0.03 0.03 0.08 0.03 0.03 0.04 0.06 0.03 0.01 0.19 2006 0.07 0.05 0.03 0.04 0.14 0.02 0.00 0.01 0.03 0.01 0.10 2007 0.01 0.04 0.03 0.02 0.04 0.08 0.03 0.03 0.03 0.03 0.17 2008 0.02 0.04 0.04 0.05 0.03 0.03 0.07 0.04 0.02 0.03 0.17 2009 0.02 0.03 0.06 0.06 0.03 0.05 0.04 0.05 0.03 0.03 0.17 2010 0.04 0.03 0.04 0.04 0.04 0.03 0.04 0.04 0.06 0.03 0.17 2011 0.02 0.05 0.04 0.05 0.04 0.06 0.03 0.03 0.03 0.04 0.16 2012 0.02 0.03 0.05 0.04 0.05 0.02 0.05 0.02 0.01 0.02 0.16 2013 0.01 0.02 0.04 0.07 0.06 0.07 0.05 0.04 0.02 0.03 0.14 2014 0.01 0.02 0.04 0.05 0.05 0.06 0.04 0.03 0.04 0.03 0.18 2015 0.01 0.02 0.02 0.04 0.03 0.08 0.04 0.04 0.03 0.04 0.18 2016 0.02 0.04 0.04 0.03 0.04 0.03 0.06 0.03 0.02 0.01 0.21

Table 4.5 Yellowfin sole biomass estimates (t) from the annual Bering Sea shelf bottom trawl survey and upper and lower 95% confidence intervals.

Year Total Lower CI Upper CI

1982 3,377,800 2,571,000 4,184,600 1983 3,535,300 2,958,100 4,112,400 1984 3,141,200 2,636,800 3,645,600 1985 2,443,700 1,563,400 3,324,000 1986 1,909,900 1,480,700 2,339,000 1987 2,613,100 2,051,800 3,174,400 1988 2,402,400 1,808,400 2,996,300 1989 2,316,300 1,836,700 2,795,800 1990 2,183,800 1,886,200 2,479,400 1991 2,393,300 2,116,000 2,670,700 1992 2,172,900 1,898,900 2,690,600 1993 2,465,400 2,151,500 2,779,300 1994 2,610,500 2,266,800 2,954,100 1995 2,009,700 1,724,800 2,294,600 1996 2,298,600 1,749,900 2,847,300 1997 2,163,400 1,907,900 2,418,900 1998 2,329,600 2,033,130 2,626,070 1999 1,306,470 1,118,800 1,494,150 2000 1,581,900 1,382,000 1,781,800 2001 1,863,700 1,605,000 2,122,300 2002 2,016,700 1,740,700 2,292,700 2003 2,239,600 1,822,700 2,656,600 2004 2,530,600 2,147,900 2,913,300 2005 2,823,500 2,035,800 3,499,800 2006 2,133,070 1,818,253 2,447,932 2007 2,152,738 1,775,191 2,530,285 2008 2,099,521 1,599,100 2,600,000 2009 1,739,238 1,435,188 2,043,288 2010 2,367,830 1,807,430 2,928,230 2011 2,403,021 1,926,371 2,879,671 2012 1,951,400 1,675,982 2,226,819 2013 2,279,004 1,934,134 2,623,874 2014 2,512,250 2,058,018 2,966,482 2015 1,932,347 1,644,043 2,220,651 2016 2,859,811 2,532,202 3,187,421 2017 2,787,688 2,310,198 3,265,178

Table 4.6. Yellowfin sole population numbers-at-age (millions) estimated from the annual bottom trawl surveys, 1982-2016. females 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17+ 1979 21 113 150 442 616 386 555 801 626 528 219 274 59 35 29 15 1980 1 92 342 518 800 1055 413 661 880 651 765 285 113 33 23 23 1981 0 20 195 839 692 1321 1155 261 477 744 527 311 168 55 23 45 1982 38 183 349 1211 1485 1424 1619 843 829 832 704 409 246 159 51 84 1983 0 5 59 154 751 1413 843 1065 936 753 1155 866 295 160 60 54 1984 0 53 278 264 427 745 841 1111 1080 941 541 583 480 239 174 133 1985 0 3 105 442 587 406 632 915 441 518 545 384 298 321 205 127 1986 0 8 24 219 349 666 279 574 519 377 284 318 196 250 136 259 1987 0 0 70 120 803 458 843 259 376 599 356 449 243 270 247 688 1988 0 0 7 370 71 1495 560 557 184 239 351 208 360 273 219 886 1989 0 0 14 98 718 234 1337 593 446 74 179 308 234 238 183 565 1990 0 0 70 102 325 1066 192 1257 408 482 101 72 107 78 231 605 1991 0 10 127 248 123 405 896 151 1263 213 525 63 128 87 123 807 1992 0 19 247 485 520 213 286 938 94 825 75 309 129 137 170 715 1993 0 24 100 357 634 434 269 224 1314 78 866 157 165 69 68 674 1994 0 54 95 223 518 905 555 482 284 1170 516 44 274 142 42 588 1995 0 19 153 288 181 889 627 274 135 25 634 21 561 104 80 512 1996 0 16 154 809 288 279 434 517 206 146 151 602 116 637 47 619 1997 0 18 324 502 725 256 239 506 228 114 176 184 500 44 314 533 1998 0 10 83 479 420 900 260 203 370 413 369 170 176 265 67 1167 1999 0 3 65 198 175 185 727 104 107 245 190 186 72 102 175 425 2000 0 11 54 248 208 304 444 537 189 198 237 219 65 117 145 572 2001 0 1 71 239 522 248 403 415 654 374 83 191 154 127 189 617 2002 0 16 123 170 255 778 346 290 229 457 221 91 307 116 152 805 2003 0 15 115 241 251 287 1143 225 279 286 251 103 115 170 168 943 2004 10 33 192 430 560 441 217 966 221 212 218 219 106 20 167 1020 2005 0 53 167 194 602 433 213 487 834 196 144 191 324 170 53 1332 2006 0 67 302 376 276 634 470 176 325 738 133 133 71 156 175 514 2007 0 37 515 348 376 277 504 308 124 227 504 119 137 127 105 724 2008 0 24 115 736 621 546 359 355 198 117 259 350 153 79 85 732 2009 5 38 204 204 1187 609 488 259 210 218 129 138 196 88 43 444 2010 0 33 328 386 438 895 554 517 329 335 155 166 135 173 99 684 2011 0 14 243 539 707 463 769 410 457 204 226 149 142 145 186 619 2012 10 50 229 394 503 293 243 752 256 334 106 156 37 150 128 547 2013 0 4 88 269 420 531 256 221 409 406 358 119 135 133 133 770 2014 0 0 37 421 384 248 420 231 228 523 341 160 144 228 34 819 2015 0 23 3 167 467 350 308 287 249 149 282 258 135 99 80 592 2016 1 32 71 45 164 743 565 403 364 300 144 245 230 140 163 1027

Table 4.6.(continued) males year/age 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17+ 1979 21 115 143 390 381 303 583 847 604 406 349 247 54 76 29 36 1980 20 78 306 632 853 1221 457 558 616 568 444 370 147 18 8 8 1981 0 50 200 1047 640 1280 858 394 372 546 534 266 66 83 55 12 1982 89 193 428 1780 1781 1059 1673 644 774 463 471 482 302 8 24 8 1983 0 1 65 183 724 1729 808 1049 676 699 722 566 425 550 77 51 1984 0 68 246 323 497 734 830 612 788 718 358 379 201 316 122 106 1985 0 41 172 419 559 263 652 527 401 451 360 224 260 157 112 65 1986 0 13 47 108 373 652 262 327 284 335 211 205 115 210 82 252 1987 0 5 41 106 838 467 673 445 328 277 210 147 106 142 185 600 1988 0 2 10 435 49 1163 553 443 85 187 28 177 336 189 28 599 1989 0 2 23 181 788 177 1306 513 357 135 50 103 54 204 35 478 1990 0 11 47 121 316 888 195 1144 318 263 40 65 67 24 55 389 1991 0 0 103 354 139 275 1046 68 1137 328 244 74 64 60 53 420 1992 0 0 146 445 566 262 226 812 114 907 193 213 12 12 61 607 1993 0 20 52 233 646 393 279 247 1096 69 842 53 53 50 0 341 1994 4 22 71 166 427 953 656 308 191 822 26 622 46 132 11 303 1995 0 0 169 120 270 667 565 94 179 75 478 13 603 49 24 418 1996 0 76 95 837 244 227 425 344 331 141 139 399 61 449 125 495 1997 0 10 214 425 798 181 184 446 245 194 214 108 514 79 264 416 1998 0 48 70 351 569 832 159 226 204 272 346 140 157 191 113 814 1999 0 5 100 142 225 243 575 146 94 309 269 75 53 28 119 425 2000 0 0 36 219 259 143 509 583 78 215 133 77 92 78 66 547 2001 0 0 87 141 652 341 375 357 562 208 87 158 65 73 140 432 2002 0 58 72 158 309 758 318 333 262 442 194 120 220 161 133 507 2003 0 24 95 178 258 251 1074 238 363 53 284 173 10 71 57 682 2004 4 63 114 469 447 199 395 993 263 81 195 223 103 47 249 456 2005 0 49 166 187 474 476 204 288 972 123 142 121 133 69 93 726 2006 0 101 173 348 332 505 393 288 298 384 116 155 89 39 11 590 2007 0 58 481 352 405 284 545 209 166 252 338 101 133 72 59 620 2008 0 10 99 662 462 483 344 453 225 144 185 329 63 66 35 581 2009 0 65 144 289 946 462 555 248 249 217 78 31 195 30 29 363 2010 0 78 199 418 371 1032 462 510 171 189 159 53 117 151 78 678 2011 1 7 150 385 482 358 792 398 224 176 77 81 136 103 157 440 2012 0 69 274 352 344 273 238 425 297 179 98 67 91 34 100 2 2013 0 7 92 366 384 481 211 268 445 200 200 33 89 100 118 612 2014 0 0 0 9 366 396 286 338 310 251 400 206 193 20 192 841 2015 1 29 36 131 426 332 301 312 318 48 180 131 80 1 80 492 2016 0 43 85 20 142 704 544 402 367 125 117 227 180 88 35 859

Table 4.7 Occurrence of yellowfin sole in the Bering Sea trawl survey and collections of length and age structures and the number of otoliths aged from each survey. Total Hauls Number Hauls Hauls Number of Number Year Hauls w/Len lengths w/otoliths w/ages otoliths ages 1982 334 246 37023 35 35 744 744 1983 353 256 33924 37 37 709 709 1984 355 271 33894 56 56 821 796 1985 357 261 33824 44 43 810 802 1986 354 249 30470 34 34 739 739 1987 357 224 31241 16 16 798 798 1988 373 254 27138 14 14 543 543 1989 374 236 29672 24 24 740 740 1990 371 251 30257 28 28 792 792 1991 372 248 27986 26 26 742 742 1992 356 229 23628 16 16 606 606 1993 375 242 26651 20 20 549 549 1994 375 269 24448 14 14 526 522 1995 376 254 22116 20 20 654 647 1996 375 247 27505 16 16 729 721 1997 376 262 26034 11 11 470 466 1998 375 310 34509 15 15 575 570 1999 373 276 28431 31 31 777 770 2000 372 255 24880 20 20 517 511 2001 375 251 26558 25 25 604 593 2002 375 246 26309 32 32 738 723 2003 376 241 27135 37 37 699 695 2004 375 251 26103 26 26 725 712 2005 373 251 24658 34 34 644 635 2006 376 246 28470 39 39 428 426 2007 376 247 24790 66 66 779 772 2008 375 238 25848 65 65 858 830 2009 376 235 22018 70 70 784 752 2010 376 228 20619 77 77 841 827 2011 376 228 21665 65 64 784 753 2012 376 242 23519 72 72 993 973 2013 376 232 23261 70 70 821 803 2014 376 219 20229 52 52 799 790 2015 376 223 20830 73 73 878 875 2016 376 242 26674 69 69 884 876 2017 376 258 25767 78 896

Table 4.8 Total tonnage of yellowfin sole caught in resource assessment surveys in the eastern Bering Sea from 1977-2017. Research Year catch (t)

1977 60 1978 71 1979 147 1980 92 1981 74 1982 158 1983 254 1984 218 1985 105 1986 68 1987 92 1988 138 1989 148 1990 129 1991 118 1992 60 1993 95 1994 91 1995 95 1996 72 1997 76 1998 79 1999 61 2000 72 2001 75 2002 76 2003 78 2004 114 2005 94 2006 74 2007 74 2008 69 2009 60 2010 79 2011 77 2012 64 2013 75 2014 81 2015 64 2016 98 2017 98

Table 4.9. Mean length and weight at age for yellowfin sole (unsmoothed). average mean length at age (cm) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 males 7 11 12 14 17 20 22 24 26 27 28 29 30 30 31 31 31 32 32 32 females 10 13 15 17 20 22 25 27 29 30 31 32 33 33 33 34 34 33 34 weight at age (g) males 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 1954 0 4 15 34 60 91 125 160 195 230 263 294 322 348 372 393 412 429 444 481 1955 0 4 15 34 60 91 125 160 195 230 263 294 322 348 372 393 412 429 444 481 | 0 4 15 34 60 91 125 160 195 230 263 294 322 348 372 393 412 429 444 481 1974 0 4 15 34 60 91 125 160 195 230 263 294 322 348 372 393 412 429 444 481 1975 4 14 18 32 54 85 120 156 193 225 253 280 303 324 330 344 355 366 390 423 1976 4 14 18 32 54 85 120 156 193 225 253 280 303 324 330 344 355 366 390 423 1977 4 14 18 32 54 85 120 156 193 225 253 280 303 324 330 344 355 366 390 423 1978 4 14 18 32 54 85 120 156 193 225 253 280 303 324 330 344 355 366 390 423 1979 4 14 18 32 54 85 120 156 193 225 253 280 303 324 330 344 355 366 390 423 1980 4 14 18 32 54 85 120 156 193 225 253 280 303 324 330 344 355 366 390 423 1981 4 14 18 32 54 85 120 156 193 225 253 280 303 324 330 344 355 366 390 423 1982 4 11 25 50 83 112 133 142 158 182 196 212 218 249 403 386 386 455 532 408 1983 4 5 5 23 57 95 156 156 155 176 212 227 227 254 262 287 271 370 370 408 1984 4 10 20 31 57 121 150 181 202 193 202 213 246 252 257 262 282 415 290 370 1985 4 11 23 32 51 84 148 186 214 227 228 246 277 267 283 305 407 389 532 387 1986 4 9 18 27 34 61 98 176 217 233 239 229 271 263 258 324 265 318 300 370 1987 4 8 14 17 27 53 97 157 211 226 260 267 311 309 276 291 307 296 329 394 1988 4 7 10 18 45 75 76 138 207 242 261 304 301 297 339 304 308 315 326 386 1989 4 7 10 27 47 72 142 130 179 244 270 351 338 352 317 302 391 309 361 348 1990 4 9 16 22 44 64 98 120 175 197 273 323 341 326 337 286 348 353 343 388 1991 4 9 17 29 51 75 100 132 180 212 266 267 325 355 326 359 352 304 532 381 1992 4 9 17 28 53 86 97 125 174 208 239 264 306 508 407 395 344 360 406 360 1993 4 9 18 45 56 93 135 145 206 209 238 265 387 303 349 363 376 349 342 384 1994 4 23 32 53 76 92 116 182 198 207 259 336 311 345 345 407 356 479 349 424 1995 4 10 19 32 59 88 110 154 177 207 249 258 336 294 319 377 367 383 401 448 1996 4 10 19 32 54 107 134 163 184 215 221 264 281 295 314 326 333 418 326 435 1997 4 8 14 37 64 75 149 174 185 239 231 248 261 303 349 336 384 370 346 444 1998 4 10 20 27 49 79 113 156 208 207 259 262 289 301 291 332 330 354 350 392 1999 4 6 7 18 37 63 95 123 170 171 245 281 269 269 347 330 395 350 350 450 2000 4 10 20 36 32 64 88 133 161 284 233 271 302 255 291 331 351 349 373 385 2001 4 9 16 27 38 51 91 152 161 198 268 240 280 299 292 320 343 357 430 434 2002 4 9 18 21 57 59 81 134 188 204 241 248 269 306 303 343 336 304 368 414 2003 4 11 22 39 53 83 109 161 179 251 248 304 263 468 330 339 305 339 352 405 2004 4 7 20 40 64 94 157 157 213 266 334 310 297 356 360 338 387 414 443 446 2005 4 11 24 44 77 110 136 170 201 262 278 332 366 308 328 350 375 347 349 434 2006 4 10 19 36 71 124 139 180 207 237 233 315 330 380 385 446 369 335 382 390 2007 4 10 19 36 63 107 140 181 208 248 291 286 311 340 375 342 353 369 422 430 2008 4 8 13 29 50 91 113 181 194 252 262 289 306 364 366 369 372 374 417 481 2009 4 7 11 20 39 74 112 133 194 273 270 302 348 321 379 320 405 370 391 460 2010 4 14 18 32 54 85 120 156 193 225 253 280 303 324 330 344 355 366 390 423 2011 4 14 17 25 47 81 134 164 174 305 283 330 291 346 332 344 389 364 375 400 2012 4 14 12 27 48 83 126 181 214 249 274 296 295 341 342 382 380 388 396 400 2013 4 14 13 21 40 72 122 179 227 259 278 320 273 379 357 379 407 390 366 400 2014 4 8 11 44 34 75 150 195 246 296 313 314 330 273 385 387 400 478 436 400 2015 4 8 11 44 34 75 150 195 246 296 313 314 330 273 385 387 400 478 436 400 2016 4 8 43 57 63 82 116 171 253 319 318 331 338 346 381 383 408 434 413 460 2017 4 8 43 57 63 82 116 171 253 319 318 331 338 346 381 383 408 434 413 460

Table 4.9—(continued) Mean length and weight at age for yellowfin sole (unsmoothed). females 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 1954 4 15 34 60 91 125 160 195 230 263 294 322 348 372 393 412 429 444 481 590 | 4 15 34 60 91 125 160 195 230 263 294 322 348 372 393 412 429 444 481 590 1974 4 15 34 60 91 125 160 195 230 263 294 322 348 372 393 412 429 444 481 590 1975 8 20 31 55 84 124 165 217 266 301 341 374 407 428 443 480 483 499 590 590 1976 8 20 31 55 84 124 165 217 266 301 341 374 407 428 443 480 483 499 590 590 1977 8 20 31 55 84 124 165 217 266 301 341 374 407 428 443 480 483 499 590 590 1978 8 20 31 55 84 124 165 217 266 301 341 374 407 428 443 480 483 499 590 590 1979 8 20 31 55 84 124 165 217 266 301 341 374 407 428 443 480 483 499 590 590 1980 8 20 31 55 84 124 165 217 266 301 341 374 407 428 443 480 483 499 590 590 1981 8 20 31 55 84 124 165 217 266 301 341 374 407 428 443 480 483 499 590 590 1982 8 20 42 75 98 139 176 214 233 235 289 300 339 336 406 490 417 386 568 590 1983 10 14 26 60 103 162 185 201 243 255 280 329 395 477 539 583 578 630 685 590 1984 14 26 33 57 110 156 177 222 246 294 338 332 325 422 436 458 497 665 654 590 1985 11 16 28 46 77 177 202 251 286 302 323 371 370 421 425 499 624 600 620 590 1986 14 27 23 41 71 103 173 239 284 338 342 350 402 351 391 422 440 455 611 590 1987 10 14 20 47 55 127 179 256 317 324 373 373 385 384 422 412 458 436 523 590 1988 9 12 16 34 66 85 159 237 286 307 378 396 404 388 415 437 429 485 578 590 1989 12 21 33 67 71 112 133 197 279 339 402 430 449 456 456 456 578 476 516 590 1990 11 17 24 38 65 99 126 197 243 321 449 450 416 446 464 455 471 523 569 590 1991 11 16 23 58 56 100 142 156 238 310 370 457 446 473 474 490 492 484 598 590 1992 12 21 29 55 85 121 177 176 283 305 284 352 435 516 459 484 519 459 547 590 1993 15 28 35 64 93 155 165 232 244 301 333 368 442 452 497 499 471 538 586 590 1994 20 46 53 86 87 125 155 235 276 284 337 396 351 461 464 480 476 514 553 590 1995 12 20 28 60 84 123 160 217 284 332 340 443 384 414 454 439 619 482 589 590 1996 11 16 36 51 108 137 167 202 222 311 318 334 405 399 432 534 462 523 558 590 1997 16 34 33 72 85 157 200 236 260 292 353 373 401 469 440 490 431 515 600 590 1998 10 14 36 51 90 104 177 237 278 279 318 370 416 405 403 448 407 532 581 590 1999 9 12 18 37 67 103 131 239 284 296 328 348 384 396 416 461 502 477 639 590 2000 11 16 33 33 91 81 158 175 237 306 310 373 401 440 422 494 506 483 636 590 2001 6 6 32 41 57 83 148 179 255 305 357 372 447 415 420 422 476 522 598 590 2002 11 18 27 48 65 87 120 224 243 261 337 346 374 408 434 452 505 489 585 590 2003 9 12 31 53 86 124 156 213 289 303 344 407 425 399 434 365 438 457 536 590 2004 9 18 43 63 101 168 172 245 299 346 380 407 483 543 450 461 464 500 604 590 2005 14 26 44 78 114 152 213 238 277 337 347 397 439 461 531 522 438 539 629 590 2006 9 13 40 82 125 153 204 245 319 314 375 370 533 460 476 865 480 537 691 590 2007 11 16 36 66 115 173 198 244 316 311 362 358 417 461 462 497 491 611 640 590 2008 13 24 28 54 98 129 199 226 286 320 355 384 442 434 471 530 530 552 630 590 2009 6 9 18 45 69 127 163 239 306 322 375 416 381 413 473 736 539 491 679 590 2010 8 20 31 55 84 124 165 217 266 301 341 374 407 428 443 480 483 499 590 590 2011 8 18 25 56 80 126 188 205 327 332 372 403 415 440 426 369 491 542 590 590 2012 8 12 26 49 81 144 169 256 313 341 349 445 459 471 476 444 527 525 590 590 2013 8 12 21 35 92 125 182 261 305 364 410 426 464 456 451 507 494 532 590 590 2014 6 8 11 18 34 74 145 203 260 305 376 367 405 410 488 519 483 581 548 590 2015 6 8 11 18 34 74 145 203 260 305 376 367 405 410 488 519 483 581 548 590 2016 6 8 32 50 66 74 112 186 338 372 412 408 455 456 485 508 515 532 555 590 2017 6 8 32 50 66 74 112 186 338 372 412 408 455 456 485 508 515 532 555 590

Table 4.10. Female yellowfin sole proportion mature at age from Nichol (1995) and TenBrink and Wilderbuer (2015). Age 1992, 1993 2012 samples samples Combined 1 0.00 0 0 2 0.00 0 0 3 0.001 0 0 4 0.004 0 0 5 0.008 0 0 6 0.020 0.01 0.01 7 0.046 0.03 0.04 8 0.104 0.09 0.10 9 0.217 0.21 0.21 10 0.397 0.43 0.41 11 0.612 0.68 0.65 12 0.790 0.86 0.83 13 0.899 0.94 0.92 14 0.955 0.98 0.97 15 0.981 0.99 0.99 16 0.992 1.0 1.0 17 0.997 1.0 1.0 18 1.0 1.0 1.0 19 1.0 1.0 1.0 20 1.0 1.0 1.0

Table 4.11. Key equations used in the population dynamics model. τ = = t N t ,1 Rt R0 e 2 , τ t ~ N(0,δ R ) Recruitment 1956-75

τ t N t ,1 =Rt = Rγ e 2 , τ t ~ N(0,δ R ) Recruitment 1976-96

Ft ,a − C = (1 − e zt ,a )N t ,a Z t ,a t ,a Catch in year t for age a fish

− N = N e zt ,a t +1,a+1 t ,a Numbers of fish in year t+1 at age a

− − N = N e zt , A−1 + N e zt , A t +1, A t , A−1 t , A Numbers of fish in the “plus group”

S = N W φ t ∑ t ,a t ,a a Spawning biomass

Z = F + M t ,a t ,a Total mortality in year t at age a

F = µ F ε t Ft ,as a exp F 2F , ε t ~N ( o ,σ ) Fishing mortality

1 s = a + −α +βa 1 (e ) Age-specific fishing selectivity

C = C t ∑ t ,a Total catch in numbers

Ct, a P = C t ,a t Proportion at age in catch

SurB = q N W v t ∑ t ,a t ,a a Survey biomass

Table 4.11—continued.

2 0.5(lnqest ,t−ln q prior ) qprior = λ 2 survey catchability prior (when estimated) σ q

0.5(ln m − ln m )2 mprior = λ est prior 2 natural mortality prior (when estimated) σ m

endyear − 20 − 2 2 1 recruitment likelihood reclike = λ( R − R ) + (R − R ) + ) ∑ i ∑ init init,a endyear − i=1965 a=1 1 2(( ∑ R− Ri )) i=1965 n +1

endyear 2 catchlike = λ ∑(lnCobs,i − lnCest,i ) catch likelihood i=startyear

∧ (ln B − ln B)2 surveylike = λ survey likelihood 2σ 2

∧

Pt,a SurvAgelike = ∑ mt P t,a ln survey age composition likelihood i,t Pt,a

∧

Pt,a FishAgelike = ∑ mt P t,a ln fishery age composition likelihood i,t Pt,a

Table 4.12. Variables used in the population dynamics model. Variables Description

Rt Age 1 recruitment in year t

R0 Geometric mean value of age 1 recruitment, 1956-75

Rγ Geometric mean value of age 1 recruitment, 1976-2014

τ t Recruitment deviation in year t N t ,a Number of fish in year t at age a C t ,a Catch numbers of fish in year t at age a P t ,a Proportion of the numbers of fish age a in year t

Ct Total catch numbers in year t W t ,a Mean body weight (kg) of fish age a in year t φ a Proportion of mature females at age a

Ft ,a Instantaneous annual fishing mortality of age a fish in year t M Instantaneous natural mortality, assumed constant over all ages and years

Zt ,a Instantaneous total mortality for age a fish in year t

sa Age-specific fishing gear selectivity µ F Median year-effect of fishing mortality

F εt The residual year-effect of fishing mortality

νa Age-specific survey selectivity α Slope parameter in the logistic selectivity equation β Age at 50% selectivity parameter in the logistic selectivity equation

σ t Standard error of the survey biomass in year t

Table 4.13. Models evaluated for stock productivity in the 2017 stock assessment of yellowfin sole

Model Model 14_2 14_1

Years included 1955-2012 1978-2012

Fmsy 0.19 0.12

Bmsy (t) 333,700 454,000

ABC (t) 471,300 277,500

OFL (t) 476,800 306,700 Buffer between ABC and OFL 1% 11%

Table 4-14. Model estimates of annual average fishing mortality for male and female yellowfin sole. Females year/age 7 8 9 10 11 12 13 14 15 16 17 18 19 20 1964 0.082 0.179 0.269 0.315 0.330 0.335 0.337 0.337 0.337 0.337 0.337 0.337 0.337 0.337 1965 0.012 0.044 0.114 0.189 0.225 0.237 0.240 0.240 0.241 0.241 0.241 0.241 0.241 0.241 1966 0.018 0.053 0.139 0.270 0.375 0.426 0.444 0.449 0.451 0.452 0.452 0.452 0.452 0.452 1967 0.027 0.078 0.194 0.362 0.497 0.562 0.586 0.594 0.597 0.597 0.598 0.598 0.598 0.598 1968 0.011 0.027 0.062 0.129 0.228 0.328 0.397 0.433 0.449 0.455 0.458 0.458 0.458 0.458 1969 0.057 0.205 0.442 0.578 0.617 0.625 0.627 0.627 0.628 0.628 0.628 0.628 0.628 0.628 1970 0.347 0.608 0.650 0.654 0.655 0.655 0.655 0.655 0.655 0.655 0.655 0.655 0.655 0.655 1971 0.383 0.583 0.605 0.607 0.607 0.607 0.607 0.607 0.607 0.607 0.607 0.607 0.607 0.607 1972 0.000 0.000 0.000 0.000 0.000 0.001 0.003 0.010 0.034 0.106 0.250 0.250 0.250 0.250 1973 0.018 0.064 0.178 0.318 0.394 0.419 0.426 0.427 0.428 0.428 0.428 0.428 0.428 0.428 1974 0.004 0.014 0.038 0.078 0.116 0.135 0.143 0.145 0.146 0.146 0.146 0.146 0.146 0.146 1975 0.018 0.056 0.101 0.123 0.129 0.130 0.131 0.131 0.131 0.131 0.131 0.131 0.131 0.131 1976 0.011 0.029 0.059 0.091 0.111 0.121 0.124 0.126 0.126 0.126 0.126 0.126 0.126 0.126 1977 0.026 0.036 0.046 0.052 0.055 0.057 0.058 0.059 0.059 0.059 0.059 0.059 0.059 0.059 1978 0.032 0.063 0.091 0.107 0.113 0.115 0.115 0.115 0.116 0.116 0.116 0.116 0.116 0.116 1979 0.019 0.037 0.053 0.062 0.065 0.067 0.067 0.067 0.067 0.067 0.067 0.067 0.067 0.067 1980 0.014 0.024 0.038 0.051 0.062 0.069 0.073 0.075 0.076 0.076 0.076 0.076 0.076 0.076 1981 0.014 0.024 0.036 0.046 0.053 0.057 0.058 0.059 0.060 0.060 0.060 0.060 0.060 0.060 1982 0.015 0.026 0.035 0.041 0.043 0.044 0.044 0.044 0.044 0.044 0.044 0.044 0.044 0.044 1983 0.022 0.034 0.042 0.044 0.045 0.046 0.046 0.046 0.046 0.046 0.046 0.046 0.046 0.046 1984 0.017 0.034 0.052 0.063 0.068 0.070 0.071 0.071 0.071 0.071 0.071 0.071 0.071 0.071 1985 0.020 0.041 0.067 0.088 0.099 0.103 0.105 0.106 0.106 0.106 0.106 0.106 0.106 0.106 1986 0.025 0.058 0.084 0.094 0.097 0.098 0.098 0.098 0.098 0.098 0.098 0.098 0.098 0.098 1987 0.009 0.021 0.042 0.066 0.082 0.091 0.094 0.096 0.096 0.096 0.096 0.096 0.096 0.096 1988 0.011 0.032 0.068 0.100 0.115 0.120 0.122 0.122 0.122 0.122 0.122 0.122 0.122 0.122 1989 0.004 0.013 0.035 0.064 0.082 0.089 0.091 0.091 0.092 0.092 0.092 0.092 0.092 0.092 1990 0.004 0.012 0.024 0.034 0.038 0.039 0.040 0.040 0.040 0.040 0.040 0.040 0.040 0.040 1991 0.006 0.014 0.025 0.035 0.041 0.043 0.044 0.045 0.045 0.045 0.045 0.045 0.045 0.045 1992 0.011 0.025 0.044 0.059 0.068 0.071 0.073 0.073 0.073 0.073 0.074 0.074 0.074 0.074 1993 0.008 0.014 0.022 0.032 0.041 0.047 0.051 0.053 0.054 0.055 0.055 0.055 0.055 0.055 1994 0.014 0.031 0.049 0.060 0.064 0.065 0.066 0.066 0.066 0.066 0.066 0.066 0.066 0.066 1995 0.016 0.033 0.047 0.054 0.056 0.057 0.057 0.057 0.057 0.057 0.057 0.057 0.057 0.057 1996 0.017 0.029 0.042 0.051 0.057 0.060 0.061 0.062 0.062 0.062 0.062 0.062 0.062 0.062 1997 0.021 0.037 0.056 0.072 0.082 0.088 0.091 0.093 0.093 0.093 0.094 0.094 0.094 0.094 1998 0.016 0.029 0.041 0.048 0.051 0.053 0.053 0.053 0.053 0.054 0.054 0.054 0.054 0.054 1999 0.002 0.007 0.016 0.027 0.035 0.039 0.041 0.041 0.041 0.041 0.041 0.041 0.041 0.041 2000 0.003 0.008 0.019 0.033 0.043 0.048 0.050 0.050 0.050 0.050 0.050 0.050 0.050 0.050 2001 0.006 0.013 0.023 0.031 0.035 0.037 0.037 0.037 0.038 0.038 0.038 0.038 0.038 0.038 2002 0.003 0.008 0.018 0.030 0.037 0.040 0.041 0.042 0.042 0.042 0.042 0.042 0.042 0.042 2003 0.005 0.012 0.023 0.032 0.037 0.039 0.040 0.040 0.040 0.040 0.040 0.040 0.040 0.040 2004 0.006 0.013 0.022 0.030 0.034 0.036 0.037 0.037 0.037 0.037 0.037 0.037 0.037 0.037 2005 0.010 0.019 0.029 0.038 0.044 0.047 0.048 0.049 0.049 0.049 0.049 0.049 0.049 0.049 2006 0.032 0.042 0.046 0.046 0.046 0.046 0.046 0.046 0.046 0.046 0.046 0.046 0.046 0.046 2007 0.013 0.026 0.042 0.053 0.059 0.062 0.063 0.063 0.063 0.063 0.063 0.063 0.063 0.063 2008 0.016 0.034 0.053 0.065 0.070 0.071 0.072 0.072 0.072 0.072 0.072 0.072 0.072 0.072 2009 0.010 0.025 0.043 0.051 0.054 0.055 0.055 0.055 0.055 0.055 0.055 0.055 0.055 0.055 2010 0.011 0.023 0.039 0.050 0.055 0.057 0.058 0.058 0.058 0.058 0.058 0.058 0.058 0.058 2011 0.012 0.028 0.049 0.064 0.072 0.075 0.076 0.076 0.076 0.076 0.076 0.076 0.076 0.076 2012 0.012 0.027 0.045 0.060 0.069 0.072 0.073 0.074 0.074 0.074 0.074 0.074 0.074 0.074 2013 0.005 0.018 0.044 0.072 0.086 0.090 0.092 0.092 0.092 0.092 0.092 0.092 0.092 0.092 2014 0.006 0.017 0.040 0.066 0.082 0.089 0.091 0.092 0.092 0.092 0.092 0.092 0.092 0.092 2015 0.004 0.009 0.020 0.038 0.059 0.075 0.083 0.087 0.089 0.090 0.090 0.090 0.090 0.090 2016 0.007 0.015 0.028 0.045 0.063 0.075 0.083 0.086 0.088 0.089 0.089 0.089 0.089 0.089 2017 0.009 0.022 0.043 0.061 0.070 0.074 0.075 0.075 0.075 0.076 0.076 0.076 0.076 0.076

Table 4.14 continued. Males year/age 7 8 9 10 11 12 13 14 15 16 17 18 19 20 1964 0.337 0.337 0.337 0.337 0.337 0.337 0.337 0.337 0.337 0.337 0.337 0.337 0.337 0.337 1965 0.005 0.024 0.087 0.178 0.225 0.237 0.240 0.240 0.241 0.241 0.241 0.241 0.241 0.241 1966 0.021 0.093 0.261 0.397 0.440 0.450 0.451 0.452 0.452 0.452 0.452 0.452 0.452 0.452 1967 0.137 0.397 0.556 0.591 0.597 0.598 0.598 0.598 0.598 0.598 0.598 0.598 0.598 0.598 1968 0.043 0.184 0.373 0.444 0.457 0.460 0.460 0.460 0.460 0.460 0.460 0.460 0.460 0.460 1969 0.007 0.039 0.176 0.438 0.584 0.620 0.626 0.627 0.628 0.628 0.628 0.628 0.628 0.628 1970 0.000 0.001 0.006 0.027 0.115 0.335 0.548 0.630 0.650 0.654 0.655 0.655 0.655 0.655 1971 0.371 0.586 0.606 0.607 0.607 0.607 0.607 0.607 0.607 0.607 0.607 0.607 0.607 0.607 1972 0.114 0.337 0.474 0.504 0.508 0.509 0.509 0.509 0.509 0.509 0.509 0.509 0.509 0.509 1973 0.114 0.351 0.420 0.427 0.428 0.428 0.428 0.428 0.428 0.428 0.428 0.428 0.428 0.428 1974 0.083 0.125 0.141 0.145 0.146 0.146 0.146 0.146 0.146 0.146 0.146 0.146 0.146 0.146 1975 0.047 0.103 0.126 0.130 0.131 0.131 0.131 0.131 0.131 0.131 0.131 0.131 0.131 0.131 1976 0.010 0.028 0.061 0.096 0.115 0.123 0.125 0.126 0.126 0.126 0.126 0.126 0.126 0.126 1977 0.009 0.026 0.046 0.055 0.058 0.059 0.059 0.059 0.059 0.059 0.059 0.059 0.059 0.059 1978 0.025 0.051 0.080 0.100 0.109 0.113 0.115 0.115 0.115 0.116 0.116 0.116 0.116 0.116 1979 0.018 0.036 0.052 0.061 0.065 0.067 0.067 0.067 0.067 0.067 0.067 0.067 0.067 0.067 1980 0.007 0.011 0.018 0.028 0.038 0.049 0.059 0.065 0.070 0.073 0.074 0.074 0.074 0.074 1981 0.012 0.020 0.029 0.039 0.047 0.052 0.056 0.058 0.059 0.059 0.059 0.059 0.059 0.059 1982 0.022 0.032 0.039 0.042 0.044 0.044 0.044 0.044 0.044 0.044 0.044 0.044 0.044 0.044 1983 0.024 0.036 0.042 0.045 0.045 0.046 0.046 0.046 0.046 0.046 0.046 0.046 0.046 0.046 1984 0.023 0.046 0.062 0.069 0.070 0.071 0.071 0.071 0.071 0.071 0.071 0.071 0.071 0.071 1985 0.036 0.073 0.096 0.104 0.106 0.106 0.106 0.106 0.106 0.106 0.106 0.106 0.106 0.106 1986 0.034 0.072 0.091 0.097 0.098 0.098 0.098 0.098 0.098 0.098 0.098 0.098 0.098 0.098 1987 0.015 0.050 0.083 0.094 0.096 0.096 0.096 0.096 0.096 0.096 0.096 0.096 0.096 0.096 1988 0.015 0.055 0.100 0.118 0.122 0.122 0.122 0.122 0.122 0.122 0.122 0.122 0.122 0.122 1989 0.004 0.015 0.044 0.074 0.087 0.091 0.091 0.092 0.092 0.092 0.092 0.092 0.092 0.092 1990 0.008 0.022 0.034 0.038 0.040 0.040 0.040 0.040 0.040 0.040 0.040 0.040 0.040 0.040 1991 0.008 0.024 0.039 0.044 0.045 0.045 0.045 0.045 0.045 0.045 0.045 0.045 0.045 0.045 1992 0.017 0.039 0.059 0.069 0.072 0.073 0.073 0.073 0.074 0.074 0.074 0.074 0.074 0.074 1993 0.009 0.015 0.024 0.034 0.043 0.048 0.052 0.054 0.055 0.055 0.055 0.055 0.055 0.055 1994 0.018 0.039 0.056 0.063 0.065 0.066 0.066 0.066 0.066 0.066 0.066 0.066 0.066 0.066 1995 0.019 0.038 0.051 0.056 0.057 0.057 0.057 0.057 0.057 0.057 0.057 0.057 0.057 0.057 1996 0.026 0.040 0.052 0.058 0.060 0.062 0.062 0.062 0.062 0.062 0.062 0.062 0.062 0.062 1997 0.026 0.048 0.069 0.083 0.089 0.092 0.093 0.093 0.094 0.094 0.094 0.094 0.094 0.094 1998 0.007 0.021 0.038 0.049 0.052 0.053 0.053 0.054 0.054 0.054 0.054 0.054 0.054 0.054 1999 0.002 0.004 0.010 0.019 0.029 0.036 0.039 0.040 0.041 0.041 0.041 0.041 0.041 0.041 2000 0.003 0.007 0.017 0.031 0.042 0.047 0.049 0.050 0.050 0.050 0.050 0.050 0.050 0.050 2001 0.001 0.004 0.008 0.015 0.024 0.031 0.035 0.036 0.037 0.037 0.038 0.038 0.038 0.038 2002 0.002 0.008 0.021 0.035 0.040 0.041 0.042 0.042 0.042 0.042 0.042 0.042 0.042 0.042 2003 0.006 0.017 0.031 0.038 0.039 0.040 0.040 0.040 0.040 0.040 0.040 0.040 0.040 0.040 2004 0.005 0.011 0.021 0.030 0.034 0.036 0.037 0.037 0.037 0.037 0.037 0.037 0.037 0.037 2005 0.011 0.023 0.035 0.043 0.047 0.049 0.049 0.049 0.049 0.049 0.049 0.049 0.049 0.049 2006 0.028 0.043 0.046 0.046 0.046 0.046 0.046 0.046 0.046 0.046 0.046 0.046 0.046 0.046 2007 0.020 0.040 0.054 0.061 0.063 0.063 0.063 0.063 0.063 0.063 0.063 0.063 0.063 0.063 2008 0.018 0.039 0.058 0.067 0.071 0.072 0.072 0.072 0.072 0.072 0.072 0.072 0.072 0.072 2009 0.008 0.019 0.034 0.046 0.052 0.054 0.054 0.055 0.055 0.055 0.055 0.055 0.055 0.055 2010 0.016 0.036 0.050 0.056 0.058 0.058 0.058 0.058 0.058 0.058 0.058 0.058 0.058 0.058 2011 0.017 0.036 0.057 0.069 0.074 0.075 0.076 0.076 0.076 0.076 0.076 0.076 0.076 0.076 2012 0.018 0.040 0.060 0.070 0.073 0.074 0.074 0.074 0.074 0.074 0.074 0.074 0.074 0.074 2013 0.007 0.021 0.049 0.074 0.087 0.091 0.092 0.092 0.092 0.092 0.092 0.092 0.092 0.092 2014 0.008 0.021 0.043 0.067 0.082 0.089 0.091 0.092 0.092 0.092 0.092 0.092 0.092 0.092 2015 0.005 0.010 0.019 0.033 0.051 0.067 0.078 0.084 0.087 0.089 0.089 0.089 0.089 0.089 2016 0.007 0.014 0.026 0.043 0.061 0.074 0.082 0.086 0.088 0.089 0.089 0.089 0.089 0.089 2017 0.015 0.037 0.059 0.071 0.074 0.075 0.075 0.076 0.076 0.076 0.076 0.076 0.076 0.076

Table 4.15. Model estimates of yellowfin sole full selection fishing mortality and exploitation rate (catch/total biomass). Year Full selection F Exploitation Rate 1974 0.15 0.03 1975 0.13 0.04 1976 0.13 0.03 1977 0.06 0.02 1978 0.12 0.05 1979 0.07 0.03 1980 0.08 0.03 1981 0.06 0.03 1982 0.04 0.03 1983 0.05 0.03 1984 0.07 0.05 1985 0.11 0.06 1986 0.10 0.06 1987 0.10 0.06 1988 0.12 0.07 1989 0.09 0.05 1990 0.04 0.03 1991 0.04 0.03 1992 0.07 0.05 1993 0.06 0.03 1994 0.07 0.04 1995 0.06 0.04 1996 0.06 0.04 1997 0.09 0.06 1998 0.05 0.04 1999 0.04 0.03 2000 0.05 0.03 2001 0.04 0.02 2002 0.04 0.03 2003 0.04 0.03 2004 0.04 0.02 2005 0.05 0.03 2006 0.05 0.03 2007 0.06 0.04 2008 0.07 0.05 2009 0.05 0.04 2010 0.06 0.04 2011 0.08 0.05 2012 0.07 0.05 2013 0.09 0.06 2014 0.09 0.06 2015 0.09 0.05 2016 0.09 0.05 2017 0.08 0.05

Table 4.16 Model estimates of yellowfin sole age-specific selectivities for the survey and fishery (ages 4 to 20 from left to right).

4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 survey females 1982-2017 0.0 0.0 0.0 0.1 0.2 0.3 0.6 0.8 0.9 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 survey males 0.0 0.0 0.0 0.1 0.2 0.4 0.5 0.7 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 fishery females 1964 0.0 0.0 0.1 0.2 0.5 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1965 0.0 0.0 0.0 0.1 0.2 0.5 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1966 0.0 0.0 0.0 0.0 0.1 0.3 0.6 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1967 0.0 0.0 0.0 0.0 0.1 0.3 0.6 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1968 0.0 0.0 0.0 0.0 0.1 0.1 0.3 0.5 0.7 0.9 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1969 0.0 0.0 0.0 0.1 0.3 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1970 0.0 0.0 0.1 0.5 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1971 0.0 0.0 0.1 0.6 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1972 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.2 0.5 0.5 0.5 0.5 1973 0.0 0.0 0.0 0.0 0.1 0.4 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1974 0.0 0.0 0.0 0.0 0.1 0.3 0.5 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1975 0.0 0.0 0.0 0.1 0.4 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1976 0.0 0.0 0.0 0.1 0.2 0.5 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1977 0.1 0.1 0.3 0.4 0.6 0.8 0.9 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1978 0.0 0.0 0.1 0.3 0.5 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1979 0.0 0.0 0.1 0.3 0.5 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1980 0.0 0.0 0.1 0.2 0.3 0.5 0.7 0.8 0.9 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1981 0.0 0.1 0.1 0.2 0.4 0.6 0.8 0.9 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1982 0.0 0.1 0.2 0.3 0.6 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1983 0.0 0.1 0.2 0.5 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1984 0.0 0.0 0.1 0.2 0.5 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1985 0.0 0.0 0.1 0.2 0.4 0.6 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1986 0.0 0.0 0.1 0.3 0.6 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1987 0.0 0.0 0.0 0.1 0.2 0.4 0.7 0.9 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1988 0.0 0.0 0.0 0.1 0.3 0.6 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1989 0.0 0.0 0.0 0.0 0.1 0.4 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1990 0.0 0.0 0.0 0.1 0.3 0.6 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1991 0.0 0.0 0.1 0.1 0.3 0.6 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1992 0.0 0.0 0.1 0.2 0.3 0.6 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1993 0.0 0.0 0.1 0.1 0.2 0.4 0.6 0.7 0.9 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1994 0.0 0.0 0.1 0.2 0.5 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1995 0.0 0.0 0.1 0.3 0.6 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1996 0.0 0.1 0.1 0.3 0.5 0.7 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1997 0.0 0.1 0.1 0.2 0.4 0.6 0.8 0.9 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1998 0.0 0.1 0.1 0.3 0.5 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1999 0.0 0.0 0.0 0.1 0.2 0.4 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2000 0.0 0.0 0.0 0.1 0.2 0.4 0.7 0.9 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2001 0.0 0.0 0.1 0.1 0.3 0.6 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2002 0.0 0.0 0.0 0.1 0.2 0.4 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2003 0.0 0.0 0.0 0.1 0.3 0.6 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2004 0.0 0.0 0.1 0.1 0.3 0.6 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2005 0.0 0.0 0.1 0.2 0.4 0.6 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2006 0.0 0.1 0.3 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2007 0.0 0.0 0.1 0.2 0.4 0.7 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2008 0.0 0.0 0.1 0.2 0.5 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2009 0.0 0.0 0.0 0.2 0.5 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2010 0.0 0.0 0.1 0.2 0.4 0.7 0.9 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2011 0.0 0.0 0.1 0.2 0.4 0.6 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2012 0.0 0.0 0.1 0.2 0.4 0.6 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2013 0.0 0.0 0.0 0.1 0.2 0.5 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2014 0.0 0.0 0.0 0.1 0.2 0.4 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2015 0.0 0.0 0.0 0.0 0.1 0.2 0.4 0.7 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2016 0.0 0.0 0.0 0.1 0.2 0.3 0.5 0.7 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2017 0.0 0.0 0.0 0.1 0.3 0.6 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0

Table 4.16 (continued) Model estimates of yellowfin sole age-specific selectivities for the survey and fishery (ages 4 to 20 from left to right). fishery males 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 1964 0.0 0.0 0.0 0.0 0.1 0.4 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1965 0.0 0.0 0.0 0.0 0.1 0.4 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1966 0.0 0.0 0.0 0.0 0.2 0.6 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1967 0.0 0.0 0.0 0.2 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1968 0.0 0.0 0.0 0.1 0.4 0.8 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1969 0.0 0.0 0.0 0.0 0.1 0.3 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1970 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.2 0.5 0.8 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1971 0.0 0.0 0.1 0.6 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1972 0.0 0.0 0.0 0.2 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1973 0.0 0.0 0.0 0.3 0.8 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1974 0.0 0.1 0.2 0.6 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1975 0.0 0.0 0.1 0.4 0.8 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1976 0.0 0.0 0.0 0.1 0.2 0.5 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1977 0.0 0.0 0.0 0.2 0.4 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1978 0.0 0.0 0.1 0.2 0.4 0.7 0.9 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1979 0.0 0.0 0.1 0.3 0.5 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1980 0.0 0.0 0.1 0.1 0.1 0.2 0.4 0.5 0.6 0.8 0.9 0.9 0.9 1.0 1.0 1.0 1.0 1981 0.0 0.1 0.1 0.2 0.3 0.5 0.6 0.8 0.9 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1982 0.0 0.1 0.3 0.5 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1983 0.0 0.1 0.2 0.5 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1984 0.0 0.0 0.1 0.3 0.6 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1985 0.0 0.0 0.1 0.3 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1986 0.0 0.0 0.1 0.3 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1987 0.0 0.0 0.0 0.2 0.5 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1988 0.0 0.0 0.0 0.1 0.4 0.8 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1989 0.0 0.0 0.0 0.0 0.2 0.5 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1990 0.0 0.0 0.1 0.2 0.5 0.8 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1991 0.0 0.0 0.0 0.2 0.5 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1992 0.0 0.0 0.1 0.2 0.5 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1993 0.0 0.0 0.1 0.2 0.3 0.4 0.6 0.8 0.9 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1994 0.0 0.0 0.1 0.3 0.6 0.8 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1995 0.0 0.0 0.1 0.3 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1996 0.0 0.1 0.2 0.4 0.6 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1997 0.0 0.1 0.1 0.3 0.5 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1998 0.0 0.0 0.0 0.1 0.4 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1999 0.0 0.0 0.0 0.0 0.1 0.2 0.5 0.7 0.9 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2000 0.0 0.0 0.0 0.1 0.1 0.3 0.6 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2001 0.0 0.0 0.0 0.0 0.1 0.2 0.4 0.6 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2002 0.0 0.0 0.0 0.0 0.2 0.5 0.8 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2003 0.0 0.0 0.0 0.1 0.4 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2004 0.0 0.0 0.0 0.1 0.3 0.6 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2005 0.0 0.0 0.1 0.2 0.5 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2006 0.0 0.0 0.2 0.6 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2007 0.0 0.0 0.1 0.3 0.6 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2008 0.0 0.0 0.1 0.3 0.5 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2009 0.0 0.0 0.1 0.1 0.3 0.6 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2010 0.0 0.0 0.1 0.3 0.6 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2011 0.0 0.0 0.1 0.2 0.5 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2012 0.0 0.0 0.1 0.2 0.5 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2013 0.0 0.0 0.0 0.1 0.2 0.5 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2014 0.0 0.0 0.0 0.1 0.2 0.5 0.7 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2015 0.0 0.0 0.0 0.1 0.1 0.2 0.4 0.6 0.7 0.9 0.9 1.0 1.0 1.0 1.0 1.0 1.0 2016 0.0 0.0 0.0 0.1 0.2 0.3 0.5 0.7 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2017 0.0 0.0 0.1 0.2 0.5 0.8 0.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0

Table 4.17. Model estimates of yellowfin sole age 2+ total biomass (t) and begin-year female spawning biomass (t) from the 2016 and 2017 stock assessments. 2017Assessment 2016 Assessment Female spawning Lower Upper Total Lower Upper Female spawning Total Year biomass 95%C.I. 95%C.I. biomass 95%C.I. 95%C.I. biomass biomass 1964 142,369 125,963 158,775 926,625 884,358 968,892 17,615 839,742 1965 169,571 150,673 188,469 901,174 859,348 943,000 36,707 835,631 1966 207,104 181,164 233,044 936,828 894,264 979,392 61,107 879,970 1967 218,877 183,738 254,016 911,246 868,430 954,062 75,435 863,836 1968 213,928 172,597 255,259 823,838 782,109 865,567 74,113 782,492 1969 197,480 159,473 235,487 850,296 806,122 894,470 69,945 810,677 1970 135,238 107,904 162,572 813,647 767,283 860,011 65,929 786,026 1971 87,750 68,217 107,284 862,710 810,862 914,558 59,749 846,563 1972 71,363 52,436 90,290 936,838 876,587 997,089 41,419 909,321 1973 78,284 55,940 100,627 1,188,580 1,117,114 1,260,046 48,795 1,155,700 1974 84,991 62,369 107,612 1,433,880 1,350,985 1,516,775 64,968 1,397,720 1975 134,520 104,490 164,550 1,786,070 1,687,158 1,884,982 114,443 1,739,260 1976 194,457 159,757 229,157 2,091,310 1,979,840 2,202,780 175,884 2,035,950 1977 285,756 244,715 326,797 2,400,420 2,276,574 2,524,266 267,530 2,336,020 1978 400,220 353,682 446,758 2,694,380 2,558,675 2,830,085 381,170 2,620,880 1979 515,975 465,098 566,852 2,853,520 2,707,666 2,999,374 494,992 2,771,670 1980 644,788 589,440 700,136 3,034,890 2,879,623 3,190,157 620,393 2,944,900 1981 763,587 704,136 823,038 3,200,280 3,035,796 3,364,764 735,618 3,103,120 1982 830,159 769,672 890,646 3,312,110 3,142,696 3,481,524 799,728 3,208,630 1983 930,442 866,389 994,495 3,289,120 3,117,812 3,460,428 895,921 3,183,300 1984 1,009,100 942,343 1,075,857 3,509,840 3,324,897 3,694,783 971,246 3,393,380 1985 1,054,930 984,923 1,124,937 3,516,680 3,324,359 3,709,001 1,013,620 3,394,790 1986 1,040,470 969,028 1,111,912 3,228,140 3,041,303 3,414,977 996,871 3,108,320 1987 1,032,280 957,877 1,106,683 3,183,200 2,990,263 3,376,137 986,120 3,058,180 1988 973,826 899,973 1,047,679 3,082,600 2,889,542 3,275,658 927,181 2,955,620 1989 944,673 869,393 1,019,953 3,130,950 2,926,591 3,335,309 896,354 2,994,610 1990 953,446 877,432 1,029,460 2,993,920 2,791,865 3,195,975 903,497 2,858,500 1991 1,030,640 950,675 1,110,605 3,106,100 2,897,247 3,314,953 977,265 2,964,280 1992 1,108,300 1,022,799 1,193,801 3,303,480 3,081,401 3,525,559 1,051,080 3,150,890 1993 1,139,450 1,049,929 1,228,971 3,328,080 3,099,130 3,557,030 1,079,390 3,167,600 1994 1,139,730 1,049,752 1,229,708 3,362,290 3,130,320 3,594,260 1,078,550 3,194,550 1995 1,135,560 1,044,219 1,226,901 3,135,510 2,911,867 3,359,153 1,072,910 2,972,780 1996 1,068,660 980,760 1,156,560 3,047,450 2,827,286 3,267,614 1,007,480 2,881,690 1997 1,029,840 942,754 1,116,926 3,056,250 2,832,945 3,279,555 968,198 2,881,350 1998 964,342 879,785 1,048,899 2,782,490 2,569,490 2,995,490 903,440 2,612,680 1999 953,817 869,562 1,038,072 2,599,520 2,395,766 2,803,274 891,856 2,434,810 2000 939,002 855,138 1,022,866 2,645,900 2,441,086 2,850,714 876,306 2,472,620 2001 932,963 849,579 1,016,347 2,571,130 2,369,891 2,772,369 868,908 2,397,250 2002 929,799 846,867 1,012,731 2,612,290 2,410,173 2,814,407 864,250 2,430,820 2003 937,347 854,321 1,020,373 2,820,560 2,606,587 3,034,533 869,246 2,618,170 2004 966,374 881,636 1,051,112 3,028,200 2,801,621 3,254,779 893,962 2,805,970 2005 981,900 896,204 1,067,596 3,138,190 2,904,329 3,372,051 905,612 2,906,560 2006 1,001,710 914,164 1,089,256 3,121,280 2,886,123 3,356,437 920,437 2,887,410 2007 1,007,020 918,540 1,095,500 3,131,800 2,892,122 3,371,478 921,166 2,895,700 2008 984,018 895,586 1,072,450 3,002,470 2,766,978 3,237,962 894,603 2,771,050 2009 950,705 863,010 1,038,400 2,834,320 2,603,218 3,065,422 858,763 2,606,720 2010 928,940 841,575 1,016,305 2,903,440 2,665,625 3,141,255 835,187 2,670,900 2011 910,298 823,033 997,563 2,936,040 2,690,395 3,181,685 815,498 2,701,250 2012 897,681 809,011 986,351 2,927,810 2,676,751 3,178,869 802,230 2,693,730 2013 894,342 802,405 986,279 2,883,080 2,627,632 3,138,528 799,268 2,647,970 2014 858,579 764,911 952,247 2,680,370 2,430,474 2,930,266 764,979 2,449,450 2015 861,299 763,454 959,144 2,699,440 2,438,694 2,960,186 767,803 2,451,240 2016 876,687 775,173 978,201 2,852,570 2,552,951 3,152,189 775,148 2,457,260 2017 884,750 780,860 988,640 2,878,150 2,535,096 3,221,204

Table 4.18—Model estimates of yellowfin sole population numbers at age (billions) for 1954-2017. Female s 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 1954 1.04 0.70 0.30 0.22 0.22 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 1955 0.84 0.92 0.62 0.27 0.20 0.19 0.18 0.18 0.18 0.18 0.18 0.18 0.18 0.17 0.17 0.17 0.17 0.17 0.17 1956 0.73 0.75 0.81 0.55 0.24 0.18 0.17 0.16 0.16 0.16 0.16 0.16 0.15 0.15 0.15 0.15 0.15 0.15 0.15 1957 2.95 0.65 0.66 0.72 0.49 0.21 0.16 0.15 0.14 0.14 0.14 0.14 0.14 0.13 0.13 0.13 0.13 0.13 0.13 1958 2.33 2.62 0.58 0.59 0.64 0.43 0.19 0.14 0.13 0.12 0.12 0.12 0.12 0.12 0.12 0.12 0.12 0.12 0.12 1959 1.49 2.07 2.32 0.51 0.52 0.57 0.38 0.16 0.12 0.12 0.11 0.11 0.10 0.10 0.10 0.10 0.10 0.10 0.10 1960 1.00 1.32 1.83 2.06 0.45 0.46 0.50 0.33 0.14 0.10 0.09 0.08 0.08 0.08 0.08 0.08 0.08 0.08 0.08 1961 0.51 0.89 1.17 1.62 1.82 0.40 0.41 0.44 0.29 0.11 0.07 0.05 0.04 0.04 0.04 0.04 0.04 0.04 0.04 1962 0.95 0.46 0.79 1.04 1.44 1.62 0.36 0.36 0.39 0.24 0.09 0.04 0.02 0.01 0.01 0.01 0.01 0.01 0.01 1963 0.46 0.85 0.40 0.70 0.92 1.28 1.44 0.32 0.32 0.34 0.21 0.07 0.02 0.00 0.00 0.00 0.00 0.00 0.00 1964 0.42 0.41 0.75 0.36 0.62 0.81 1.09 1.16 0.23 0.22 0.22 0.13 0.04 0.02 0.00 0.00 0.00 0.00 0.00 1965 0.59 0.37 0.37 0.67 0.32 0.54 0.70 0.89 0.86 0.16 0.14 0.14 0.09 0.03 0.01 0.00 0.00 0.00 0.00 1966 0.61 0.52 0.33 0.32 0.59 0.28 0.48 0.61 0.76 0.68 0.12 0.10 0.10 0.06 0.02 0.01 0.00 0.00 0.00 1967 1.25 0.54 0.46 0.29 0.29 0.52 0.25 0.42 0.51 0.59 0.46 0.07 0.06 0.06 0.03 0.01 0.00 0.00 0.00 1968 1.91 1.11 0.48 0.41 0.26 0.25 0.46 0.21 0.34 0.38 0.36 0.25 0.04 0.03 0.03 0.02 0.01 0.00 0.00 1969 1.96 1.70 0.99 0.42 0.36 0.23 0.22 0.40 0.19 0.29 0.29 0.26 0.16 0.02 0.02 0.02 0.01 0.00 0.00 1970 2.58 1.74 1.50 0.88 0.38 0.32 0.20 0.19 0.29 0.11 0.14 0.14 0.12 0.08 0.01 0.01 0.01 0.00 0.00 1971 2.87 2.29 1.54 1.33 0.78 0.33 0.27 0.13 0.09 0.13 0.05 0.07 0.06 0.06 0.03 0.00 0.00 0.00 0.00 1972 2.25 2.54 2.03 1.37 1.18 0.68 0.28 0.16 0.06 0.04 0.07 0.02 0.03 0.03 0.03 0.02 0.00 0.00 0.00 1973 1.56 2.00 2.26 1.80 1.21 1.05 0.61 0.24 0.14 0.06 0.04 0.06 0.02 0.03 0.03 0.02 0.01 0.00 0.00 1974 2.10 1.38 1.77 2.00 1.60 1.07 0.93 0.53 0.20 0.11 0.04 0.02 0.03 0.01 0.02 0.02 0.01 0.01 0.00 1975 2.47 1.86 1.23 1.57 1.78 1.42 0.95 0.82 0.46 0.17 0.09 0.03 0.02 0.03 0.01 0.01 0.01 0.01 0.01 1976 1.62 2.19 1.65 1.09 1.39 1.57 1.25 0.83 0.69 0.37 0.14 0.07 0.02 0.01 0.02 0.01 0.01 0.01 0.01 1977 2.04 1.44 1.94 1.46 0.96 1.23 1.39 1.10 0.71 0.57 0.30 0.11 0.05 0.02 0.01 0.02 0.01 0.01 0.01 1978 1.34 1.81 1.28 1.72 1.29 0.85 1.08 1.20 0.94 0.60 0.48 0.25 0.09 0.04 0.01 0.01 0.01 0.00 0.01 1979 0.85 1.18 1.61 1.13 1.52 1.14 0.74 0.93 1.00 0.76 0.48 0.38 0.20 0.07 0.04 0.01 0.01 0.01 0.00 1980 1.64 0.76 1.05 1.42 1.00 1.34 1.00 0.65 0.79 0.84 0.63 0.40 0.32 0.17 0.06 0.03 0.01 0.01 0.01

Table 4.18—Model estimates of yellowfin sole population numbers at age (billions) for 1954-2017 (continued). 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 1981 1.21 1.45 0.67 0.93 1.26 0.89 1.18 0.88 0.56 0.68 0.71 0.53 0.33 0.26 0.14 0.05 0.02 0.01 0.00 0.02 1982 3.51 1.08 1.29 0.59 0.82 1.11 0.78 1.04 0.76 0.48 0.57 0.60 0.44 0.28 0.22 0.11 0.04 0.02 0.01 0.02 1983 0.65 3.11 0.95 1.14 0.53 0.73 0.98 0.68 0.89 0.65 0.41 0.49 0.51 0.38 0.24 0.19 0.10 0.03 0.02 0.02 1984 2.89 0.58 2.76 0.85 1.01 0.46 0.64 0.85 0.58 0.76 0.55 0.35 0.41 0.43 0.32 0.20 0.16 0.08 0.03 0.04 1985 1.00 2.56 0.51 2.45 0.75 0.89 0.41 0.56 0.73 0.49 0.63 0.46 0.29 0.34 0.35 0.26 0.16 0.13 0.07 0.05 1986 0.76 0.88 2.27 0.45 2.17 0.66 0.79 0.36 0.48 0.61 0.40 0.51 0.37 0.23 0.27 0.28 0.21 0.13 0.10 0.10 1987 1.04 0.68 0.78 2.02 0.40 1.92 0.58 0.68 0.30 0.39 0.49 0.32 0.41 0.29 0.18 0.22 0.23 0.17 0.11 0.16 1988 1.42 0.92 0.60 0.70 1.79 0.36 1.70 0.51 0.59 0.25 0.32 0.40 0.26 0.33 0.24 0.15 0.18 0.18 0.14 0.21 1989 1.42 1.26 0.82 0.53 0.62 1.58 0.31 1.49 0.44 0.49 0.20 0.25 0.31 0.20 0.26 0.19 0.12 0.14 0.14 0.27 1990 0.71 1.26 1.12 0.73 0.47 0.55 1.40 0.28 1.30 0.38 0.41 0.17 0.21 0.25 0.17 0.21 0.15 0.09 0.11 0.34 1991 0.79 0.63 1.12 0.99 0.64 0.42 0.48 1.24 0.24 1.13 0.32 0.35 0.14 0.18 0.22 0.14 0.18 0.13 0.08 0.38 1992 1.76 0.70 0.56 0.99 0.88 0.57 0.37 0.43 1.08 0.21 0.96 0.28 0.30 0.12 0.15 0.18 0.12 0.15 0.11 0.39 1993 1.05 1.56 0.62 0.49 0.88 0.78 0.50 0.33 0.37 0.92 0.18 0.80 0.23 0.24 0.10 0.12 0.15 0.10 0.13 0.41 1994 0.89 0.93 1.38 0.55 0.44 0.78 0.69 0.44 0.28 0.32 0.79 0.15 0.68 0.19 0.20 0.08 0.10 0.13 0.08 0.45 1995 0.90 0.79 0.83 1.22 0.49 0.39 0.68 0.60 0.38 0.24 0.27 0.66 0.12 0.56 0.16 0.17 0.07 0.09 0.11 0.44 1996 2.24 0.80 0.70 0.73 1.09 0.43 0.34 0.60 0.52 0.32 0.20 0.22 0.55 0.10 0.47 0.13 0.14 0.06 0.07 0.46 1997 0.97 1.98 0.71 0.62 0.65 0.96 0.38 0.30 0.52 0.44 0.27 0.17 0.19 0.46 0.09 0.39 0.11 0.12 0.05 0.44 1998 0.80 0.86 1.76 0.63 0.55 0.57 0.84 0.33 0.25 0.43 0.36 0.22 0.14 0.15 0.37 0.07 0.32 0.09 0.10 0.40 1999 1.00 0.71 0.76 1.56 0.56 0.49 0.50 0.73 0.28 0.22 0.37 0.31 0.19 0.12 0.13 0.31 0.06 0.27 0.08 0.41 2000 1.41 0.89 0.63 0.68 1.38 0.49 0.43 0.45 0.65 0.25 0.19 0.31 0.26 0.16 0.10 0.11 0.27 0.05 0.23 0.42 2001 0.90 1.25 0.79 0.56 0.60 1.22 0.44 0.38 0.39 0.56 0.21 0.16 0.26 0.22 0.13 0.08 0.09 0.22 0.04 0.54 2002 1.25 0.80 1.11 0.70 0.50 0.53 1.08 0.39 0.33 0.34 0.48 0.18 0.14 0.23 0.19 0.11 0.07 0.08 0.19 0.50 2003 1.21 1.11 0.71 0.98 0.62 0.44 0.47 0.96 0.34 0.29 0.29 0.41 0.16 0.12 0.19 0.16 0.10 0.06 0.07 0.59 2004 1.98 1.08 0.98 0.63 0.87 0.55 0.39 0.42 0.84 0.29 0.25 0.25 0.35 0.13 0.10 0.16 0.14 0.08 0.05 0.56 2005 0.91 1.76 0.96 0.87 0.56 0.77 0.49 0.34 0.36 0.73 0.25 0.21 0.21 0.30 0.11 0.08 0.14 0.12 0.07 0.52 2006 1.12 0.80 1.56 0.85 0.77 0.49 0.68 0.43 0.30 0.31 0.62 0.22 0.18 0.18 0.25 0.10 0.07 0.12 0.10 0.50 2007 1.44 1.00 0.71 1.38 0.75 0.68 0.43 0.58 0.36 0.25 0.27 0.53 0.18 0.15 0.15 0.22 0.08 0.06 0.10 0.51 2008 1.33 1.28 0.88 0.63 1.22 0.66 0.60 0.38 0.50 0.31 0.21 0.22 0.44 0.15 0.13 0.13 0.18 0.07 0.05 0.50 2009 1.47 1.18 1.13 0.78 0.56 1.08 0.59 0.53 0.32 0.42 0.26 0.18 0.18 0.36 0.13 0.11 0.11 0.15 0.06 0.46 2010 1.73 1.30 1.05 1.00 0.70 0.50 0.96 0.51 0.45 0.27 0.36 0.22 0.15 0.15 0.30 0.11 0.09 0.09 0.12 0.43 2011 0.62 1.53 1.16 0.93 0.89 0.62 0.44 0.84 0.45 0.39 0.23 0.30 0.18 0.12 0.13 0.25 0.09 0.07 0.07 0.46 2012 0.47 0.55 1.36 1.03 0.82 0.79 0.54 0.38 0.72 0.38 0.32 0.19 0.25 0.15 0.10 0.11 0.21 0.07 0.06 0.44 2013 1.05 0.42 0.48 1.20 0.91 0.73 0.70 0.48 0.33 0.61 0.31 0.27 0.16 0.20 0.12 0.08 0.09 0.17 0.06 0.41 2014 1.31 0.93 0.37 0.43 1.07 0.81 0.64 0.61 0.42 0.28 0.51 0.26 0.22 0.13 0.16 0.10 0.07 0.07 0.14 0.38 2015 1.13 1.16 0.83 0.33 0.38 0.95 0.71 0.57 0.53 0.35 0.23 0.41 0.21 0.18 0.10 0.13 0.08 0.05 0.06 0.42 2016 1.20 1.00 1.03 0.73 0.29 0.34 0.84 0.63 0.50 0.46 0.30 0.20 0.34 0.17 0.14 0.08 0.11 0.06 0.04 0.39 2017 1.21 1.06 0.89 0.91 0.65 0.26 0.30 0.74 0.55 0.43 0.39 0.25 0.16 0.28 0.14 0.12 0.07 0.09 0.05 0.35

Table 4.18. Model estimates of yellowfin sole population numbers at age (billions) for 1954-2017 (continued). 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 1954 1.04 0.37 0.25 0.21 0.21 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 1955 0.84 0.92 0.33 0.22 0.19 0.19 0.18 0.18 0.18 0.18 0.18 0.18 0.18 0.17 0.17 0.17 0.17 0.17 0.17 0.35 1956 0.73 0.75 0.81 0.29 0.20 0.17 0.17 0.16 0.16 0.16 0.16 0.16 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.46 1957 2.95 0.65 0.66 0.72 0.26 0.17 0.15 0.15 0.14 0.14 0.14 0.14 0.14 0.13 0.13 0.13 0.13 0.13 0.13 0.53 1958 2.33 2.62 0.58 0.59 0.64 0.23 0.15 0.13 0.13 0.12 0.12 0.12 0.12 0.12 0.12 0.12 0.12 0.12 0.12 0.58 1959 1.49 2.07 2.32 0.51 0.52 0.57 0.20 0.14 0.12 0.11 0.11 0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.60 1960 1.00 1.32 1.83 2.06 0.45 0.46 0.50 0.18 0.11 0.09 0.09 0.08 0.08 0.08 0.08 0.08 0.08 0.08 0.08 0.53 1961 0.51 0.89 1.17 1.62 1.82 0.40 0.39 0.39 0.12 0.06 0.05 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.30 1962 0.95 0.46 0.79 1.03 1.41 1.51 0.28 0.19 0.11 0.02 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.05 1963 0.46 0.83 0.38 0.50 0.23 0.02 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1964 0.42 0.41 0.74 0.34 0.45 0.20 0.02 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1965 0.59 0.38 0.37 0.65 0.24 0.28 0.13 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1966 0.61 0.52 0.33 0.32 0.58 0.21 0.25 0.11 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1967 1.25 0.54 0.46 0.29 0.29 0.51 0.19 0.22 0.09 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1968 1.91 1.11 0.48 0.41 0.26 0.25 0.44 0.14 0.13 0.05 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1969 1.96 1.70 0.99 0.42 0.36 0.23 0.22 0.38 0.11 0.08 0.03 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1970 2.58 1.74 1.50 0.88 0.38 0.32 0.21 0.20 0.32 0.08 0.05 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1971 2.87 2.29 1.54 1.33 0.78 0.33 0.28 0.18 0.17 0.28 0.07 0.04 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1972 2.25 2.54 2.03 1.37 1.18 0.69 0.28 0.17 0.09 0.08 0.14 0.03 0.02 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1973 1.56 2.00 2.26 1.80 1.21 1.05 0.60 0.22 0.11 0.05 0.05 0.07 0.02 0.01 0.00 0.00 0.00 0.00 0.00 0.00 1974 2.10 1.38 1.77 2.00 1.60 1.07 0.92 0.47 0.14 0.06 0.03 0.03 0.04 0.01 0.01 0.00 0.00 0.00 0.00 0.00 1975 2.47 1.86 1.23 1.57 1.77 1.40 0.92 0.75 0.37 0.11 0.05 0.02 0.02 0.03 0.01 0.00 0.00 0.00 0.00 0.00 1976 1.62 2.19 1.65 1.09 1.39 1.57 1.23 0.78 0.60 0.29 0.08 0.04 0.02 0.02 0.03 0.01 0.00 0.00 0.00 0.00 1977 2.04 1.44 1.94 1.46 0.97 1.23 1.39 1.08 0.67 0.50 0.23 0.07 0.03 0.01 0.01 0.02 0.00 0.00 0.00 0.00 1978 1.34 1.81 1.28 1.72 1.30 0.86 1.09 1.22 0.94 0.57 0.42 0.19 0.06 0.03 0.01 0.01 0.02 0.00 0.00 0.00 1979 0.85 1.18 1.61 1.13 1.52 1.15 0.75 0.94 1.03 0.77 0.46 0.33 0.15 0.04 0.02 0.01 0.01 0.01 0.00 0.00 1980 1.64 0.76 1.05 1.42 1.00 1.35 1.01 0.65 0.81 0.86 0.64 0.38 0.28 0.13 0.04 0.02 0.01 0.01 0.01 0.00 1981 1.21 1.45 0.67 0.93 1.26 0.89 1.19 0.89 0.57 0.70 0.75 0.55 0.32 0.23 0.11 0.03 0.01 0.01 0.01 0.01 1982 3.51 1.08 1.29 0.59 0.82 1.12 0.78 1.04 0.77 0.49 0.60 0.63 0.46 0.27 0.19 0.09 0.03 0.01 0.01 0.01 1983 0.65 3.11 0.95 1.14 0.53 0.73 0.98 0.68 0.90 0.66 0.42 0.51 0.54 0.39 0.23 0.16 0.08 0.02 0.01 0.02 1984 2.89 0.58 2.76 0.85 1.01 0.46 0.64 0.85 0.58 0.76 0.56 0.36 0.43 0.45 0.33 0.19 0.14 0.06 0.02 0.02 1985 1.00 2.56 0.51 2.45 0.75 0.89 0.41 0.55 0.72 0.48 0.63 0.46 0.29 0.36 0.38 0.27 0.16 0.11 0.05 0.03 1986 0.76 0.88 2.27 0.45 2.17 0.66 0.78 0.35 0.46 0.58 0.39 0.50 0.37 0.23 0.28 0.30 0.22 0.13 0.09 0.07 1987 1.04 0.68 0.78 2.02 0.40 1.92 0.58 0.67 0.29 0.37 0.47 0.31 0.41 0.30 0.19 0.23 0.24 0.17 0.10 0.13 1988 1.42 0.92 0.60 0.70 1.79 0.36 1.70 0.51 0.57 0.24 0.30 0.38 0.25 0.33 0.24 0.15 0.18 0.19 0.14 0.19 1989 1.42 1.26 0.82 0.53 0.62 1.59 0.31 1.48 0.43 0.46 0.19 0.23 0.29 0.20 0.26 0.19 0.12 0.14 0.15 0.26 1990 0.71 1.26 1.12 0.73 0.47 0.55 1.41 0.28 1.29 0.36 0.37 0.15 0.19 0.24 0.16 0.21 0.15 0.10 0.12 0.33 1991 0.79 0.63 1.12 0.99 0.64 0.42 0.48 1.24 0.24 1.11 0.31 0.32 0.13 0.16 0.20 0.14 0.18 0.13 0.08 0.38 1992 1.76 0.70 0.56 0.99 0.88 0.57 0.37 0.43 1.07 0.21 0.94 0.26 0.27 0.11 0.14 0.17 0.12 0.15 0.11 0.39 1993 1.05 1.56 0.62 0.49 0.88 0.78 0.50 0.32 0.36 0.89 0.17 0.78 0.22 0.22 0.09 0.11 0.14 0.09 0.12 0.41 1994 0.89 0.93 1.38 0.55 0.44 0.78 0.69 0.44 0.28 0.31 0.77 0.14 0.66 0.18 0.19 0.08 0.09 0.12 0.08 0.45 1995 0.90 0.79 0.83 1.22 0.49 0.39 0.68 0.60 0.38 0.24 0.26 0.64 0.12 0.55 0.15 0.16 0.06 0.08 0.10 0.44 1996 2.24 0.80 0.70 0.73 1.09 0.43 0.34 0.60 0.51 0.32 0.20 0.22 0.53 0.10 0.46 0.13 0.13 0.05 0.07 0.45 1997 0.97 1.98 0.71 0.62 0.65 0.96 0.38 0.29 0.51 0.43 0.27 0.17 0.18 0.44 0.08 0.38 0.11 0.11 0.04 0.43

Table 4.18. Model estimates of yellowfin sole population numbers at age (billions) for 1954-2017 (continued). 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 1998 0.80 0.86 1.76 0.63 0.55 0.57 0.84 0.33 0.25 0.42 0.35 0.22 0.13 0.15 0.36 0.07 0.31 0.09 0.09 0.38 1999 1.00 0.71 0.76 1.56 0.56 0.49 0.51 0.74 0.28 0.21 0.35 0.30 0.18 0.11 0.12 0.30 0.06 0.26 0.07 0.40 2000 1.41 0.89 0.63 0.68 1.38 0.49 0.43 0.45 0.65 0.25 0.19 0.31 0.25 0.16 0.10 0.11 0.26 0.05 0.22 0.40 2001 0.90 1.25 0.79 0.56 0.60 1.23 0.44 0.38 0.40 0.57 0.21 0.16 0.26 0.21 0.13 0.08 0.09 0.22 0.04 0.52 2002 1.25 0.80 1.11 0.70 0.50 0.53 1.09 0.39 0.34 0.35 0.50 0.19 0.14 0.22 0.18 0.11 0.07 0.08 0.19 0.48 2003 1.21 1.11 0.71 0.98 0.62 0.44 0.47 0.96 0.34 0.29 0.30 0.42 0.16 0.12 0.19 0.16 0.10 0.06 0.06 0.57 2004 1.98 1.08 0.98 0.63 0.87 0.55 0.39 0.42 0.84 0.29 0.25 0.25 0.36 0.13 0.10 0.16 0.13 0.08 0.05 0.54 2005 0.91 1.76 0.96 0.87 0.56 0.77 0.49 0.34 0.36 0.73 0.25 0.21 0.22 0.31 0.12 0.08 0.14 0.11 0.07 0.50 2006 1.12 0.80 1.56 0.85 0.77 0.49 0.68 0.43 0.30 0.31 0.62 0.21 0.18 0.18 0.26 0.10 0.07 0.12 0.10 0.48 2007 1.44 1.00 0.71 1.38 0.75 0.68 0.43 0.59 0.36 0.25 0.26 0.52 0.18 0.15 0.16 0.22 0.08 0.06 0.10 0.49 2008 1.33 1.28 0.88 0.63 1.22 0.67 0.60 0.38 0.50 0.30 0.21 0.22 0.44 0.15 0.13 0.13 0.18 0.07 0.05 0.49 2009 1.47 1.18 1.13 0.78 0.56 1.08 0.59 0.52 0.32 0.42 0.25 0.17 0.18 0.36 0.12 0.11 0.11 0.15 0.06 0.45 2010 1.73 1.30 1.05 1.00 0.70 0.50 0.96 0.52 0.46 0.28 0.35 0.21 0.15 0.15 0.30 0.10 0.09 0.09 0.13 0.42 2011 0.62 1.53 1.16 0.93 0.89 0.62 0.44 0.84 0.44 0.39 0.23 0.30 0.18 0.12 0.13 0.25 0.09 0.07 0.07 0.46 2012 0.47 0.55 1.36 1.03 0.82 0.79 0.54 0.38 0.72 0.37 0.32 0.19 0.24 0.15 0.10 0.10 0.21 0.07 0.06 0.44 2013 1.05 0.42 0.48 1.20 0.91 0.73 0.69 0.47 0.33 0.60 0.31 0.26 0.16 0.20 0.12 0.08 0.09 0.17 0.06 0.41 2014 1.31 0.93 0.37 0.43 1.07 0.81 0.64 0.61 0.41 0.28 0.49 0.25 0.21 0.13 0.16 0.10 0.07 0.07 0.14 0.38 2015 1.13 1.16 0.83 0.33 0.38 0.95 0.71 0.57 0.53 0.35 0.23 0.40 0.20 0.17 0.10 0.13 0.08 0.05 0.06 0.42 2016 1.20 1.00 1.03 0.73 0.29 0.34 0.84 0.63 0.50 0.46 0.30 0.19 0.33 0.17 0.14 0.08 0.11 0.06 0.04 0.39 2017 1.21 1.06 0.89 0.91 0.65 0.26 0.30 0.74 0.55 0.43 0.39 0.25 0.16 0.27 0.13 0.11 0.07 0.09 0.05 0.35

Table 4.19. Model estimates of the number of female spawners (millions) 1964-2017. 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 1964 8.9 41.8 112.8 49.8 89.4 141.7 110.9 41.0 14.9 2.5 0.1 0.0 0.0 0.0 0.0 1965 6.0 26.6 86.8 184.1 65.4 90.5 115.4 78.4 27.3 9.6 1.6 0.1 0.0 0.0 0.0 1966 3.1 18.3 59.2 162.1 282.3 75.0 81.8 90.0 57.6 19.4 6.8 1.1 0.0 0.0 0.0 1967 5.7 9.5 40.6 109.5 242.3 298.8 58.4 52.8 53.9 33.2 11.1 3.8 0.6 0.0 0.0 1968 2.8 17.5 20.8 73.3 155.0 233.8 206.0 32.9 27.4 26.9 16.4 5.4 1.9 0.3 0.0 1969 2.5 8.6 39.1 39.5 118.3 188.8 210.8 146.7 20.7 16.1 15.4 9.2 3.0 1.1 0.2 1970 3.5 7.7 18.2 62.1 43.6 92.0 115.4 111.5 73.1 10.0 7.7 7.3 4.4 1.4 0.6 1971 3.6 10.2 12.3 19.4 55.7 31.4 54.1 59.3 54.1 34.3 4.6 3.6 3.4 2.0 0.9 1972 7.5 10.5 15.7 13.4 18.2 42.1 19.4 29.2 30.2 26.6 16.8 2.2 1.7 1.6 1.4 1973 11.5 23.2 23.7 30.7 23.0 25.2 47.7 19.2 27.2 27.0 23.1 13.4 1.6 1.2 2.1 1974 11.8 35.4 51.3 43.4 44.1 23.2 19.2 31.0 11.7 16.0 15.8 13.4 7.8 0.9 1.9 1975 15.6 36.3 79.3 98.8 71.8 56.5 23.4 16.6 25.1 9.1 12.4 12.1 10.3 6.0 2.2 1976 17.3 47.8 80.3 146.4 153.4 88.0 56.2 20.3 13.6 19.9 7.2 9.7 9.4 8.0 6.3 1977 13.6 53.1 106.3 152.3 237.3 194.2 89.2 49.3 16.8 10.8 15.7 5.6 7.6 7.4 11.2 1978 9.3 41.2 116.5 200.1 250.0 312.2 208.1 83.2 43.4 14.3 9.2 13.2 4.7 6.3 15.5 1979 12.6 28.4 89.8 213.5 313.8 311.3 316.0 183.4 69.2 34.9 11.4 7.3 10.4 3.7 17.3 1980 14.8 38.4 62.7 168.9 347.9 408.9 330.4 292.3 160.1 58.5 29.3 9.5 6.0 8.6 17.4 1981 9.7 45.2 85.2 119.4 279.5 458.0 435.4 304.9 253.6 134.2 48.6 24.1 7.8 5.0 21.4 1982 12.3 29.8 100.4 162.2 197.9 369.7 492.1 406.7 268.4 216.0 113.4 40.7 20.2 6.5 22.0 1983 8.0 37.5 66.1 190.9 269.0 263.3 401.2 465.5 363.1 232.0 185.2 96.4 34.6 17.1 24.2 1984 5.1 24.5 82.6 124.6 314.6 356.6 285.0 378.9 415.0 313.4 198.6 157.3 81.8 29.3 35.0 1985 9.8 15.6 54.2 155.8 203.2 409.2 377.3 262.7 329.5 349.2 261.6 164.5 130.1 67.6 53.1 1986 7.3 30.1 34.5 101.5 250.3 257.9 420.0 336.3 220.7 267.8 281.5 209.2 131.4 103.8 96.3 1987 21.1 22.3 66.0 63.6 160.2 315.6 265.2 376.6 284.6 180.8 217.6 227.0 168.5 105.7 160.9 1988 3.9 64.8 49.8 126.1 104.7 208.0 329.3 239.4 319.8 233.7 147.2 175.7 183.1 135.7 214.7

Table 4.19—Model estimates of the number of female spawners (millions) 1964-2017 (CONTINUED) year/age 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 1989 17.4 12.0 144.2 94.1 202.5 131.3 210.0 288.6 197.8 255.7 185.3 115.8 138.1 143.7 275.0 1990 6.0 53.6 26.9 277.7 156.1 263.2 137.1 189.9 245.9 163.1 209.1 150.4 93.8 111.8 338.8 1991 4.6 18.5 120.3 51.9 465.6 209.1 287.0 130.3 170.4 213.5 140.4 178.7 128.3 80.0 384.0 1992 6.3 14.2 41.4 231.5 87.0 623.1 227.4 271.7 116.3 147.2 183.0 119.4 151.7 108.8 393.4 1993 8.6 19.3 31.6 78.9 380.8 113.6 659.7 209.3 235.8 97.6 122.6 151.2 98.5 125.0 413.8 1994 8.5 26.3 43.0 60.8 132.5 511.0 123.5 622.0 185.6 201.9 82.9 103.2 127.1 82.7 452.2 1995 4.3 26.2 58.4 81.4 99.4 172.9 543.0 114.4 543.5 156.9 169.5 69.0 85.8 105.5 444.1 1996 4.8 13.0 58.0 110.3 133.5 130.5 185.1 506.9 100.8 463.6 132.8 142.2 57.9 71.8 460.2 1997 10.5 14.5 28.9 110.0 181.8 175.7 139.6 172.4 444.9 85.6 390.5 111.0 118.7 48.2 443.4 1998 6.3 32.1 32.0 54.3 178.7 234.5 183.3 126.4 146.8 366.4 69.9 316.2 89.8 95.9 397.1 1999 5.3 19.3 71.2 60.7 89.6 236.1 252.4 171.9 111.8 125.8 311.3 58.9 266.3 75.5 414.4 2000 5.4 16.4 43.3 138.0 102.7 120.8 258.1 239.9 154.1 97.0 108.2 265.6 50.2 226.6 416.9 2001 13.5 16.7 36.9 83.7 232.6 137.7 131.1 243.3 213.0 132.4 82.6 91.5 224.4 42.3 542.7 2002 5.8 41.4 37.4 71.1 140.6 312.5 150.6 124.9 218.7 185.4 114.3 70.8 78.2 191.6 499.7 2003 4.8 18.0 93.0 72.5 120.0 189.1 341.0 143.0 111.9 189.5 159.4 97.5 60.3 66.6 588.1 2004 6.0 14.9 40.3 179.4 121.8 161.1 206.5 324.2 128.3 97.1 163.2 136.2 83.2 51.4 557.8 2005 8.5 18.6 33.4 77.6 301.4 163.7 176.3 196.8 291.6 111.7 83.9 139.9 116.5 71.1 520.7 2006 5.4 26.0 41.4 63.9 129.5 401.9 177.5 166.3 175.0 250.9 95.3 71.0 118.2 98.4 499.5 2007 7.5 16.4 56.7 77.4 104.9 171.3 434.7 167.5 148.1 150.9 214.7 80.9 60.2 100.1 506.2 2008 7.3 23.0 36.5 107.7 127.5 137.8 182.9 403.9 146.8 125.6 127.0 179.1 67.4 50.1 504.7 2009 11.9 22.4 50.9 68.8 175.4 165.7 145.6 168.4 350.9 123.4 104.8 105.1 148.1 55.6 457.9 2010 5.5 36.6 49.9 96.9 113.3 231.0 177.8 136.3 148.8 300.1 104.7 88.2 88.4 124.3 431.2 2011 6.8 16.7 81.5 95.1 160.2 149.4 247.6 166.0 120.1 126.8 253.8 87.8 73.9 73.9 464.8 2012 8.7 20.8 37.2 154.6 155.7 208.1 157.5 227.2 143.6 100.5 105.3 209.1 72.3 60.7 442.7 2013 8.0 26.6 46.2 70.8 253.9 203.1 220.2 144.9 197.0 120.5 83.7 86.9 172.4 59.5 414.6 2014 8.9 24.6 59.5 88.6 116.3 327.4 211.2 198.8 123.4 162.3 98.5 67.8 70.4 139.5 383.5 2015 10.4 27.3 55.1 114.1 146.3 150.9 341.6 190.9 169.4 101.6 132.7 79.9 54.9 57.0 423.0 2016 3.7 32.0 61.2 106.5 192.2 195.1 161.1 313.3 163.9 140.2 83.3 107.9 64.9 44.5 389.0 2017 2.9 11.4 71.5 117.6 177.9 254.5 207.6 147.7 269.2 135.8 115.0 67.8 87.6 52.6 351.6

Table 4.20. Model estimates of yellowfin sole age 5 recruitment (millions) from the 2016 and 2017 stock assessments. Year 2017 2016 Year 2017 2016 class assessment assessment class assessment assessment 1964 733 694 1988 1,646 1,673 1965 734 742 1989 817 831 1966 1,520 1,533 1990 908 925 1967 2,316 2,331 1991 2,004 2,045 1968 2,361 2,380 1992 1,191 1,217 1969 3,100 3,126 1993 1,002 1,027 1970 3,432 3,461 1994 1,010 1,037 1971 2,691 2,716 1995 2,489 2,560 1972 1,862 1,878 1996 1,076 1,104 1973 2,496 2,519 1997 910 926 1974 2,932 2,958 1998 1,103 1,131 1975 1,929 1,947 1999 1,553 1,603 1976 2,424 2,447 2000 1,013 1,040 1977 1,584 1,599 2001 1,419 1,457 1978 1,008 1,018 2002 1,401 1,410 1979 1,937 1,956 2003 2,431 2,373 1980 1,435 1,450 2004 1,201 1,124 1981 4,138 4,182 2005 1,352 1,374 1982 765 774 2006 1,726 1,732 1983 3,407 3,448 2007 1,414 1,478 1984 1,173 1,187 2008 1,529 1,510 1985 897 909 2009 1,662 1,767 1986 1,219 1,236 2010 618 802 1987 1,659 1,684

Table 4.21. Selected parameter estimates and their standard deviation from the preferred stock assessment model. parameter value std dev parameter value std dev alpha (q-temp model) 0.11 0.04 1976 total biomass 2,091,300 56,204 beta (q-temp model) 0.10 0.01 1977 total biomass 2,400,400 63,225 mean_log_rec 0.88 0.09 1978 total biomass 2,694,400 69,811 mean sel_slope_fsh (females) 1.15 0.08 1979 total biomass 2,853,500 75,286 mean sel50_fsh (females) 8.80 0.25 1980 total biomass 3,034,900 80,233 mean sel_slope_fsh_males 1.35 0.10 1981 total biomass 3,200,300 84,440 mean sel50_fsh_males 8.10 0.24 1982 total biomass 3,312,100 86,507 sel_slope_srv (females) 1.63 0.09 1983 total biomass 3,289,100 87,202 sel50_srv (females) 5.03 0.07 1984 total biomass 3,509,800 92,839 sel_slope_srv_males -0.07 0.08 1985 total biomass 3,516,700 95,769 sel50_srv_males 0.02 0.02 1986 total biomass 3,228,100 92,811 Ricker SR logalpha -4.31 0.52 1987 total biomass 3,183,200 95,063 Ricker SR logbeta -6.30 0.32 1988 total biomass 3,082,600 94,948 Fmsy 0.11 0.04 1989 total biomass 3,131,000 99,488 log (Fmsy) -1.44 0.50 1990 total biomass 2,993,900 97,766 ABC_biomass 2017 2,557,000 144,000 1991 total biomass 3,106,100 100,820 ABC_biomass 2018 2,465,000 160,000 1992 total biomass 3,303,500 106,140 msy 404,500 146,700 1993 total biomass 3,328,100 108,860 Bmsy 456,200 83,946 1994 total biomass 3,362,300 110,410 1954 total biomass 1,995,500 112,580 1995 total biomass 3,135,500 106,550 1955 total biomass 1,975,200 101,780 1996 total biomass 3,047,400 105,130 1956 total biomass 1,952,900 91,398 1997 total biomass 3,056,200 106,830 1957 total biomass 1,934,000 82,116 1998 total biomass 2,782,500 101,640 1958 total biomass 1,948,700 73,518 1999 total biomass 2,599,500 97,406 1959 total biomass 1,986,000 64,547 2000 total biomass 2,645,900 98,153 1960 total biomass 1,915,100 54,498 2001 total biomass 2,571,100 96,456 1961 total biomass 1,594,900 41,437 2002 total biomass 2,612,300 97,314 1962 total biomass 1,206,600 24,553 2003 total biomass 2,820,600 103,810 1963 total biomass 906,560 18,470 2004 total biomass 3,028,200 110,740 1964 total biomass 926,620 18,621 2005 total biomass 3,138,200 114,760 1965 total biomass 901,170 18,555 2006 total biomass 3,121,300 115,760 1966 total biomass 936,830 19,341 2007 total biomass 3,131,800 118,000 1967 total biomass 911,250 19,602 2008 total biomass 3,002,500 116,170 1968 total biomass 823,840 19,079 2009 total biomass 2,834,300 113,680 1969 total biomass 850,300 20,485 2010 total biomass 2,903,400 116,550 1970 total biomass 813,650 21,815 2011 total biomass 2,936,000 119,650 1971 total biomass 862,710 24,803 2012 total biomass 2,927,800 122,440 1972 total biomass 936,840 28,696 2013 total biomass 2,883,100 124,240 1973 total biomass 1,188,600 34,496 2014 total biomass 2,680,400 121,130 1974 total biomass 1,433,900 40,835 2015 total biomass 2,699,400 127,400 1975 total biomass 1,786,100 48,903 2016 total biomass 2,852,600 146,360 2017 total biomass 2,878,200 162,720

Table 4.22. Projections of yellowfin sole female spawning biomass (1,000s t), catch (1,000s t) and full selection fishing mortality rate for seven future harvest scenarios. Scenarios 1 and 2 Scenario 4 Maximum Tier 3 ABC harvest permissible Maximum Tier 3 ABC harvest permissible set at F60 Female Female Year spawning biomass catch F Year spawning biomass catch F 2017 872.648 143.093 0.07 2017 872.648 143.093 0.07 2018 872.377 228.409 0.12 2018 884.502 145.995 0.07 2019 844.954 212.064 0.12 2019 890.139 149.873 0.08 2020 793.190 229.442 0.14 2020 870.836 141.006 0.08 2021 721.945 211.323 0.14 2021 835.775 135.962 0.08 2022 664.625 195.463 0.13 2022 804.738 134.927 0.08 2023 632.540 181.232 0.13 2023 790.202 134.842 0.08 2024 615.882 174.126 0.12 2024 784.202 135.041 0.08 2025 609.235 171.959 0.12 2025 784.782 135.805 0.08 2026 607.575 173.433 0.12 2026 787.834 137.642 0.08 2027 610.905 177.186 0.12 2027 794.830 139.832 0.08 2028 618.306 181.607 0.12 2028 806.787 141.935 0.08 2029 626.624 185.758 0.13 2029 820.842 144.020 0.08 2030 632.742 188.606 0.13 2030 832.341 145.736 0.08

Scenario 3 Scenario 5 Harvest at average F over the past 5 years No fishing Female Female Year spawning biomass catch F Year spawning biomass catch F 2017 872.648 143.093 0.07 2017 775.899 130.497 0.08 2018 883.837 150.570 0.08 2018 805.239 0 0 2019 887.644 153.257 0.08 2019 869.301 0 0 2020 866.878 143.954 0.08 2020 929.637 0 0 2021 830.620 138.617 0.08 2021 970.871 0 0 2022 798.650 137.418 0.08 2022 995.493 0 0 2023 783.345 137.213 0.08 2023 1018.59 0 0 2024 776.705 137.318 0.08 2024 1049.43 0 0 2025 776.723 138.021 0.08 2025 1082.95 0 0 2026 779.310 139.833 0.08 2026 1121.4 0 0 2027 785.911 142.014 0.08 2027 1162.29 0 0 2028 797.485 144.113 0.08 2028 1203.18 0 0 2029 811.164 146.197 0.08 2029 1246.29 0 0 2030 822.360 147.910 0.08 2030 1288.69 0 0

Table 4.22—continued.

Scenario 6 Scenario 7 Determination of whether yellowfin sole are Determination of whether the stock is approaching currently overfished B35=601.8 an overfished condition B35=601.8 Female Female Year spawning biomass catch F Year spawning biomass catch F 2017 872.648 143.093 0.072055 2017 872.648 143.093 0.072055 2018 865.966 271.152 0.139932 2018 872.377 228.409 0.116667 2019 821.097 246.624 0.139936 2019 844.954 212.064 0.116679 2020 760.904 220.596 0.139936 2020 793.19 229.442 0.139936 2021 694.424 204.082 0.139936 2021 721.945 211.323 0.139936 2022 642.696 183.566 0.130276 2022 664.625 195.463 0.134973 2023 616.917 173.173 0.124755 2023 632.54 181.232 0.128101 2024 605.026 168.701 0.122208 2024 615.882 174.126 0.124533 2025 601.876 168.354 0.121533 2025 609.235 171.959 0.12311 2026 602.741 171.081 0.121719 2026 607.575 173.433 0.122754 2027 607.842 175.708 0.122789 2027 610.905 177.186 0.123439 2028 616.436 180.737 0.124382 2028 618.306 181.607 0.124763 2029 625.533 185.267 0.125918 2029 626.624 185.758 0.126129 2030 632.152 188.352 0.126934 2030 632.742 188.606 0.127043

Table 4-23. Catch and bycatch (t) of other BSAI target species in the yellowfin sole directed fishery from 1992-2016 estimated from a combination of regional office reported catch and observer sampling of the catch. Species 1992 1993 1994 1995 1996 1997 1998 1999 2000 Pollock 13,100 15,253 33,200 27,041 22,254 24,100 15,335 8,701 13,425 366 1,017 1,595 346 820 386 2,382 1,627 1,998 Pacific Cod 8,700 8,723 16,415 13,181 8,684 12,825 10,224 4,380 5,192 Groundfish, General 7,990 3,847 3,983 2,904 2,565 4,755 3,580 2,524 3,541 Rock Sole 14,646 7,301 8,097 7,486 12,903 16,693 9,825 10,773 7,345 Flathead Sole 1,198 2,491 3,929 3,166 3,896 5,328 2,303 2,644 Sablefish 0 0 0 0 0 0 4 0 Atka Mackerel 1 0 0 0 1 33 0 Pacific ocean Perch 0 5 0 0 1 12 1 Rex Sole 1 1 0 20 36 1 Flounder, General 16,826 6,615 7,080 11,092 10,372 10,743 6,362 8,812 7,913 Squid 0 5 0 11 0 2 1 0 Dover Sole 35 Thornyhead 0 1 Shortraker/Rougheye 0 1 0 1 15 Butter Sole 0 3 3 2 Eulachon smelt 0 Starry Flounder 227 106 16 37 124 35 48 71 Northern Rockfish 1 0 0 Dusky Rockfish 0 Yellowfin Sole 136,804 91,931 126,163 108,493 112,818 169,661 90,062 62,941 71,479 English Sole 1 Unsp.demersal rockfish 12 0 Greenland Turbot 1 5 5 67 8 4 103 70 24 Alaska Plaice 1,579 2,709 1,130 553 6,351 2,758 2,530 2,299 , General 215 97 Skate, General 26 4 Sharpchin Rockfish 1 Bocaccio 0 Rockfish, General 0 0 3 23 0 1 3 4 Octopus 0 Smelt, general 0 0 Chilipepper 1 Eels 1 1 Lingcod Jellyfish (unspecified) 127 Snails 12 4 Sea cucumber 0 56 Korean horsehair crab 0 0 Greenling, General 0

Table 4-23. (continued).

Species 2001 2002 2003 2004 2005 2006 2007 2008 2009 Pollock 16,502 14,489 11,396 10,382 10,312 6,084 4,041 9,867 7,024 Arrowtooth Flounder 1,845 998 1,125 279 645 352 216 1,969 1,858 Pacific Cod 6,531 6,259 4,621 3,606 3,767 2,588 2,529 5,769 10,849 Groundfish, General 3,936 2,678 3,133 1,612 2,134 2,333 4003 Rock Sole 5,810 10,665 8,419 10,068 10,086 8,113 8,218 10,487 9,109 Flathead Sole 3,231 2,190 2,899 1,102 1,246 2,039 1,744 5,581 3,525 Sablefish 0 1 <1 <1 Atka Mackerel 0 0 17 110 17 <1 <1 Pacific ocean Perch 1 1 11 15 <1 <1 Rex Sole 2 0 2 Other flatfish Squid 0 0 1 <1 Dover Sole Thornyhead Shortraker/Rougheye 1 Butter Sole 7 Starry Flounder 82 133 Northern Rockfish 1 3 Dusky Rockfish 0 Yellowfin Sole 54,722 66,178 68,954 65,604 82,420 84,178 108,254 131,000 98,194 English Sole 1 Unsp.demersal rockfish Greenland Turbot 32 2 1 7 8 1 <1 4 Alaska Plaice 1,905 10,396 365 5,891 8,707 14,043 16,389 13,519 10,748 Sculpin, General 12 1,226 2,891 1,438 Skate, General 21 1,042 1,301 1,481 Sharpchin Rockfish Bocaccio Rockfish, General 1 1 3 1 1 <1 Octopus Smelt, general 0 Chilipepper Eels 0 0 Lingcod 2 Jellyfish (unspecified) 173 161 Snails 0 4 Sea cucumber 0 Korean horsehair crab 0 Kamchatka flounder

Table 4.23 (continued).

Species 2010 2011 2012 2013 2014 2015 2016

Pollock 3,749 8,685 11,226 20,246 24,712 21,282 22,324

Arrowtooth Flounder 868 2,338 995 2,012 2,216 1,686 3,252

Pacific Cod 8,649 16,300 19,230 24,382 15,217 12,169 11,988

Groundfish, General 3,048 Rock Sole 9,030 9,762 8,959 7,737 7,031 9,773 7,948

Flathead Sole 1,895 3,236 2,109 4,191 3,999 3,337 4,105

Sablefish <1 <1 <1 <1

Atka Mackerel <1 <1 <1 <1 <1 <1 Pacific ocean Perch <1 17 <1 <1 3

Rex Sole

Other flatfish 1,201 388 2,887 1,041 1,136

Squid <1

Northern Rockfish <1

Dusky Rockfish

Yellowfin Sole 90,008 136,905 133,719 147,777 139,480 107,955 107,505

English Sole

Unsp.demersal rockfish

Bocaccio 1,808 1,924 1,922 1,261

Rockfish, General 1,969 2,270 2,686 1,969

Octopus

Smelt, general

Chilipepper <1

Eels 1.3

Lingcod

Jellyfish (unspecified)

Snails

Sea cucumber

Korean horsehair crab Kamchatka flounder 110 147 427 285 Sharks 1 11

Table 4-24. Estimated non-target species catch (t) in the yellowfin sole fishery, 2003-2015 (PSC not included). Row Labels 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 Benthic urochordata 1671.6 1701.5 674.5 520.1 114.5 347.6 204.7 156.0 133.0 140.8 197.4 116.1 230.1 Birds Bivalves 1.5 1.1 1.3 0.3 0.5 1.5 1.3 1.8 1.7 0.7 1.2 0.9 1.4 unidentified 34.3 32.3 28.7 20.0 7.6 19.0 5.2 4.2 14.0 13.1 5.9 11.6 2.9 Capelin 0.0 4.5 0.0 0.1 0.3 0.2 0.3 0.7 3.8 2.3 0.2 1.3 1.8 Corals Bryozoans 0.2 0.0 1.2 9.4 0.2 8.3 0.3 0.5 0.9 0.7 3.0 0.8 0.1 Eelpouts 19.1 12.3 7.7 4.5 2.3 5.6 5.2 5.1 29.3 14.3 51.6 69.8 21.1 Eulachon 0.0 0.3 0.0 0.1 5.1 0.0 0.1 0.1 0.5 0.1 0.0 0.7 0.2 Greenlings 0.6 0.7 0.3 0.7 0.5 0.2 0.0 0.1 0.0 0.1 0.0 0.2 Grenadier 0.3 0.4 Gunnels 0.0 0.0 0.0 Hermit crab unidentified 87.9 52.0 83.6 26.9 35.8 36.6 15.4 17.0 15.9 9.9 6.3 8.6 4.1 Invertebrate unidentified 556.5 625.8 421.2 177.2 40.0 70.4 30.6 25.9 65.4 121.3 25.2 44.4 6.2 Misc crabs 14.4 21.6 11.9 10.6 28.0 14.1 11.0 11.7 20.2 18.2 39.7 19.8 18.8 Misc crustaceans 0.0 0.2 0.2 2.3 1.4 0.7 1.3 0.9 0.5 0.4 0.6 0.2 0.6 Misc fish 95.8 91.2 66.2 42.5 71.2 66.3 48.8 29.2 40.0 86.2 48.2 69.3 34.8 Misc inverts (worms etc) 0.0 0.1 0.0 0.0 0.0 0.2 0.2 0.1 0.2 0.1 0.2 0.1 0.0 Other osmerids 4.2 4.3 0.5 0.6 35.8 9.8 0.8 2.8 2.1 4.7 1.0 9.2 4.8 Pacific Sand lance 0.0 0.2 0.1 0.0 0.0 0.0 0.0 0.0 0.4 0.2 0.0 0.0 0.1 Pacific Sandfish 0.0 0.0 0.0 0.0 0.1 0.1 Pandalid shrimp 0.2 0.9 0.1 0.8 0.1 0.3 0.5 0.7 2.3 0.6 2.1 1.0 0.2 unidentified 0.0 0.1 0.0 0.4 0.1 0.2 0.1 0.1 0.2 0.1 2.0 0.1 0.1 Scypho jellies 111.9 298.7 115.6 46.8 42.4 145.8 223.2 152.4 307.2 179.3 463.2 805.0 352.0 Sea anemone unidentified 6.3 6.2 2.6 4.9 8.8 24.8 25.5 20.5 14.7 6.2 23.4 5.7 4.2 Sea pens whips 0.0 0.0 0.2 0.0 0.0 0.3 0.2 0.6 0.0 0.1 0.1 0.0 0.0 Sea star 1941.3 1868.0 1611.8 1308.6 1462.0 1829.0 683.7 795.6 1674.0 1732.7 1372.4 2106.5 1816.7 Snails 118.3 191.1 69.7 141.5 95.3 139.6 57.7 57.7 74.7 33.7 46.4 33.7 30.0 Sponge unidentified 11.3 6.8 12.2 3.1 0.4 6.8 69.4 16.5 15.1 14.1 16.6 1.5 2.2 Stichaeidae 0.1 0.0 0.0 0.8 0.2 0.0 0.2 0.4 0.1 0.1 0.4 0.5 Surf smelt 0.0 urchins dollars cucumbers 2.3 0.3 2.5 0.8 3.4 4.9 7.5 1.3 1.0 0.7 0.8 0.5 0.4 Grand Total 4678 4920 3112 2322 1957 2732 1393 1302 2417 2381 2308 3307 2534

Table 4.25--Yellowfin sole TAC and ABC levels, 1980- 2017. Total Year TAC ABC catch 1980 117,000 169,000 87,391 1981 117,000 214,500 97,301 1982 117,000 214,500 95,712 1983 117,000 214,500 108,385 1984 230,000 310,000 159,526 1985 229,900 310,000 227,107 1986 209,500 230,000 208,597 1987 187,000 187,000 181,428 1988 254,000 254,000 223,156 1989 182,675 241,000 153,170 1990 207,650 278,900 80,584 1991 135,000 250,600 95,000 1992 235,000 372,000 159,038 1993 220,000 238,000 106,101 1994 150,325 230,000 144,544 1995 190,000 277,000 124,740 1996 200,000 278,000 129,659 1997 230,000 233,000 181,389 1998 220,000 220,000 101,201 1999 207,980 212,000 67,320 2000 123,262 191,000 83,850 2001 113,000 176,000 63,395 2002 86,000 115,000 72,999 2003 83,750 114,000 74,418 2004 86,075 114,000 69,046 2005 90,686 124,000 94,683 2006 95,701 121,000 99,068 2007 136,000 225,000 121,029 2008 225,000 248,000 148,894 2009 210,000 210,000 107,528 2010 219,000 219,000 118,624 2011 196,000 239,000 151,164 2012 202,000 203,000 147,183 2013 198,000 206,000 164,944 2014 184,000 239,800 156,778 2015 149,000 248,800 126,933 2016 144,000 211,700 130,500 2017 154,000 260,800 143,000

600 catch

500 average exploitation rate 1978-2016 = 0.067 400

300

200 catch (1,000s t)

100

0 1954 1958 1962 1966 1970 1974 1978 1982 1986 1990 1994 1998 2002 2006 2010 2014 year

BSAI yellowfin sole cumulative weekly catch in 200000 2013-2017

150000 2017 ABC = 260,800

100000 2016

2017

2013 50000 2014

2015 0 0 10 20 30 40 50

Figure 4.1—Yellowfin sole annual catch (1,000s t) in the Eastern Bering Sea from 1954-20167 (top panel) and catch by week (non CDQ) from 2010 – September 2017 (bottom panel).

3000 3000 509 2500 514 males females 2000 2000 1500 1000 1000 # measured 500

0 0 20 25 30 35 40 45 20 25 30 35 40 45 Length (cm) Length (cm) 3000 513 800 516 2500 600 2000

1500 400 1000 # measured 200 500

0 0 20 25 30 35 40 45 20 25 30 35 40 45 Length (cm) Length (cm)

500 521 8000 All areas 400 6000 300

200 4000 # measured 100 2000

0 0 Length (cm) 20 25 30 35 40 45 20 25 30 35 40 45 Length (cm) Figure 4.2--Size composition of the yellowfin sole catch in 2017 (through mid-September), by subarea and total.

yellowfin sole catch by month in 2017 through September 20

January 7% September 10% February 9% August 13% March 14% July 4% June 11% April 15% May 17%

yellowfin sole catch by area in 2017 (through September 20) 517 1% 521 3% 516 6% 509 35%

514 26%

513 28%

Figure 4.3 Yellowfin sole catch by month and area in the Eastern Bering Sea in 2017.

Figure 4.4 (Fishery locations by month).

CPUE (kg/ha) 90 80 70 60 50 40 30 20 10 0 1980 1985 1990 1995 2000 2005 2010 2015

Figure 4.5. Yellowfin sole CPUE (catch per unit effort in kg/ha) from the annual Bering Sea shelf trawl surveys, 1982-2017.

Survey biomass 4500 Biomass decreased 3% from 2016 to 2017 4000 3500 3000 2500 2000 1500 1000 500 0 1980 1985 1990 1995 2000 2005 2010 2015

observed

Figure 4.6. Annual bottom trawl survey biomass point-estimates and 95% confidence intervals for yellowfin sole, 1982-2017.

Figure 4.7. Difference between the 1985-2016 average trawl survey CPUE for yellowfin sole and the 2017 survey CPUE. Open circles indicate that the magnitude of the catch was greater in 2017 than the long-term average, closed circles indicate the catch was greater in the long- term average than in 2017.

700 yfin weight at age 600

500

400 males females wt (g) wt 300

200

100

0 1 3 5 7 9 11 13 15 17 19 age

Figure 4.8 Estimates of average yellowfin sole weight-at-age (g) from trawl survey observations.

R2 = 0.79 2 4 A May SST bottom temp YFS chronology 0

2 B -2 YFS crn. -3 -2 -1 0 1 2 0 R2 = 0.65 2 Normalized index Normalized 0 -2 C -2 YFS crn. 1960 1970 1980 1990 2000 -2 -1 0 1 2 3 Temperature Year Figure 4.9. Master chronology for yellowfin sole and time series of mean summer bottom temperature and May sea surface temperature for the southeastern Bering Sea (Panel A). All data re normalized to a mean of 0 and standard deviation of 1. Correlations of chronologies with bottom temperature and sea surface temperature are shown in panels B and C, respectively. From Matta et al. 2010.

yellowfin sole length at age in age samples bottom temp 5 yr old males 3 5 yr old females 2.5 2 2 1.5 1 1 0.5 0 0 1982 1986 1990 1994 1998 2002 2006 -1 -0.5 -1 -2 -1.5 -2 -3 -2.5 -4 year -3

Figure 4.10. Yellowfin sole length-at-age anomalies, for males and females, and bottom temperature anomalies. Correspondence in these residuals is apparent with a 2-3 year lag effect from the mid-1990s to 2009. Late 1980s and early 1990s pattern may be a density-dependent response in growth from the large 1981 and 1983 year-classes.

1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014

Age 2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 3 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 4 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 5 0.1 0.1 0.1 0.0 0.0 0.0 0.0 0.1 0.0 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.0 0.0 0.0 0.0 0.1 0.1 0.1 0.1 0.1 0.1 0.0 0.1 0.1 0.0 0.0 0.0 6 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 7 0.1 0.2 0.2 0.2 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.2 0.1 0.1 0.1 0.2 0.1 0.1 0.1 0.1 0.1 0.1 0.2 0.2 0.2 0.2 0.1 0.1 0.1 0.1 0.1 0.1 0.1 8 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.1 0.1 0.1 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.1 0.2 0.1 0.1 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 9 0.2 0.2 0.2 0.3 0.2 0.3 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.3 0.3 0.3 10 0.2 0.2 0.2 0.3 0.3 0.3 0.3 0.3 0.2 0.2 0.3 0.2 0.3 0.3 0.2 0.3 0.3 0.3 0.2 0.3 0.2 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 11 0.2 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.4 0.4 12 0.3 0.3 0.3 0.3 0.3 0.4 0.4 0.4 0.4 0.4 0.3 0.3 0.3 0.3 0.3 0.4 0.3 0.3 0.3 0.4 0.3 0.3 0.4 0.3 0.4 0.4 0.4 0.4 0.3 0.4 0.3 0.4 0.4 13 0.3 0.3 0.3 0.4 0.4 0.4 0.4 0.4 0.5 0.5 0.4 0.4 0.4 0.4 0.3 0.4 0.4 0.3 0.4 0.4 0.3 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 14 0.3 0.4 0.3 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.5 0.4 0.5 0.4 0.4 0.4 0.4 0.4 0.5 0.5 0.5 15 0.3 0.5 0.4 0.4 0.4 0.4 0.4 0.5 0.4 0.5 0.5 0.5 0.5 0.4 0.4 0.5 0.4 0.4 0.4 0.4 0.4 0.4 0.5 0.5 0.5 0.5 0.4 0.4 0.4 0.4 0.5 0.5 0.5 16 0.4 0.5 0.4 0.4 0.4 0.4 0.4 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.5 0.5 0.5 0.5 0.5 0.5 0.4 0.4 0.5 0.5 0.5 17 0.5 0.6 0.5 0.5 0.4 0.4 0.4 0.5 0.5 0.5 0.5 0.5 0.5 0.4 0.5 0.5 0.4 0.5 0.5 0.4 0.5 0.4 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.4 0.5 0.5 18 0.4 0.6 0.5 0.6 0.4 0.5 0.4 0.6 0.5 0.5 0.5 0.5 0.5 0.6 0.5 0.4 0.4 0.5 0.5 0.5 0.5 0.4 0.5 0.4 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 19 0.4 0.6 0.7 0.6 0.5 0.4 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.6 0.6 0.5 0.5 0.5 0.5 0.5 0.5 20 0.6 0.7 0.7 0.6 0.6 0.5 0.6 0.5 0.6 0.6 0.5 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.5 0.6 0.6 0.7 0.6 0.6 0.7 0.6 0.6 0.6 0.6 0.6 Figure 4.11. Results show the temperature anomalies (second row at top as bars) and observed values by age and year. Shadings within the matrix reflects relative weight-at-age (within a row) with darker red being heavier than average.

temperature-catchability model result

3 1.1

1.05 2 1 1 0.95

0 0.9 19841987199019931996199920022005200820112014 0.85 -1 estimated annual q 0.8 -2 bottom temp anomaly temp bottom (deg anomaly C) 0.75

-3 0.7

Figure 4.12. Average bottom water temperature from stations less than or equal to 100 m in the Bering Sea trawl survey (bars) and the stock assessment model estimate of q for each year 1982- 2017.

8000 Estimated stock recruitment curve and points

7000 1981 6000 1983

5000 1995 4000 2003 1979 3000 Bmsy 1977 2000 1980 1982 recruitment (billions) recruitment 1978 1000

0 0 200 400 600 800 1000 1200 FSB (1,000s t)

Figure 4.13. Fit of the Ricker (1958) stock recruitment model to two distinct stock recruitment time- series data sets (top panel), and the fit to the assessment preferred model (model B, lower panel).

Model 14.2 posterior distribution of Fmsy 700

600

500

400

300

200

100

0 0 0.05 0.1 0.15 0.2 0.25 0.3

Model 14.1 posterior distribution of Fmsy 600

500

400

300

frequency 200

100

0 0 0.05 0.1 0.15 0.2 0.25 Fmsy Figure 4.14. Posterior distributions of Fmsy for the two models considered in the stock productivity analysis.

1.00E+00 males 0.00E+001954 195719561955 196019591958 196319621961 196619651964 196919681967 197219711970 19741973 19761975 19781977 19801979 19821981 19841983 19861985 19881987 19901989 19921991 19941993 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 1 3 5 7 9 11 13 15 17 19

Figure 4.15a Estimated male fishery selectivity by age and year.

1 females 19550 195819571956 196119601959 196419631962 196719661965 197019691968 19721971 19741973 19761975 19781977 19801979 19821981 19841983 19861985 19881987 19901989 19921991 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017

1 3 5 7 9 11 13 15 17 19

Figure 4.15b. Estimated female fishery selectivity by age and year.

4500 Model fit to survey biomass Average annual F and full selection F 4000 0.140 3500 0.120 3000 0.100 2500 0.080 2000 0.060 1500 biomass t) (1,000s 0.040 1000 0.020 500 0.000 0 1967 1977 1987 1997 2007 2017 1980 1985 1990 1995 2000 2005 2010 2015

observed predicted avg annual F Full selection F

4000 total biomass survey selectivity 3500 1 0.9 3000 0.8 2500 0.7 2000 0.6 0.5 fema le 1500 mal e 0.4 1000 0.3

biomass biomass (1,000s t) 500 0.2 0.1

0 proportion selected 1952 1958 1964 1970 1976 1982 1988 1994 2000 2006 2012 2018 0 1 3 5 7 9 11 13 15 17 19 year age

1400 Female spawning biomass 2017 fsb is at 1.2 B40 and 1.9 1200

1000

800

600 B40 400

fsb (1,000s t) Bmsy 200

0 1954 1959 1964 1969 1974 1979 1984 1989 1994 1999 2004 2009 2014 year Figure 4.16. Model fit to the survey biomass estimates (top left panel), model estimate of the full selection fishing mortality rate throughout the time-series (top right panel), model estimate of total biomass (middle left panel), the model estimate of survey selectivity (middle right panel) and the estimate of female spawning biomass (bottom left panel).

Fishery Fishery Fishery Fishery

0.15 0.2 1975 1979 0.15 1984 0.08 1989 0.15 0.1 0.06 0.1 0.1 females 0.04 0.05 0.05 0.05 0 0.02 -0.05 1 3 5 7 9 11 13 15 17 19 0 0 0 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 -0.1 -0.02 -0.05 -0.15 -0.05 males -0.04 -0.2 -0.1 -0.1 -0.25 -0.06 -0.3 -0.15 -0.08 -0.15

0.2 1976 0.15 1980 0.08 1985 0.15 1990 0.06 0.15 0.1 0.1 0.1 0.04 0.05 0.02 0.05 0.05 0 0 0 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 -0.02 -0.05 -0.05 0 1 3 5 7 9 11 13 15 17 19 -0.04 -0.1 -0.1 -0.05 -0.06 -0.15 -0.15 -0.08 -0.2 -0.1 -0.1 -0.2

0.2 1977 1981 1986 0.15 1991 0.15 0.1 0.15 0.1 0.08 0.05 0.1 0.1 0.06 0 0.05 0.04 0.05 1 3 5 7 9 11 13 15 17 19 0.02 -0.05 0 0 -0.1 1 3 5 7 9 11 13 15 17 19 0 -0.05 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 -0.02 -0.15 -0.04 -0.1 -0.05 -0.2 -0.06 -0.15 -0.25 -0.1 -0.08

0.2 0.15 1978 0.12 1982 0.08 1987 1992 0.1 0.15 0.06 0.1 0.08 0.1 0.06 0.04 0.05 0.05 0.04 0.02 0.02 0 0 0 0 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 -0.05 -0.02 1 3 5 7 9 11 13 15 17 19 -0.02 -0.05 -0.04 -0.04 -0.1 -0.1 -0.06 -0.06 -0.15 -0.08 -0.15 -0.1 -0.08 -0.2

1983 0.08 1988 0.15 1993 0.1 0.06 0.08 0.1 0.04 0.06 0.02 0.05 0.04 0.02 0 1 3 5 7 9 11 13 15 17 19 0 0 -0.02 1 3 5 7 9 11 13 15 17 19 -0.02 1 3 5 7 9 11 13 15 17 19 -0.04 -0.05 -0.04 -0.06 -0.1 -0.06 -0.08 -0.08 -0.1 -0.15 -0.1 Figure 4.17. Stock assessment model fit to the time-series of fishery and survey age composition, by sex.

Fishery Fishery Fishery Fishery Fishery

0.2 1994 0.12 1999 0.15 2004 0.12 2009 2014 0.15 0.1 0.1 0.15 0.08 0.1 0.08 0.1 0.1 0.06 0.06 0.05 0.04 0.04 0.05 0.05 0.02 0.02 0 0 0 0 1 3 5 7 9 11 13 15 17 19 0 1 3 5 7 9 11 13 15 17 19 -0.02 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 -0.02 -0.05 1 3 5 7 9 11 13 15 17 19 -0.04 -0.05 -0.04 -0.05 -0.06 -0.06 -0.1 -0.1 -0.08 -0.08 -0.1 -0.1 -0.15 -0.1 -0.15 f_obs f_est m_obs m_est

0.2 1995 0.12 2000 0.15 2005 0.15 2010 2015 0.1 0.15 0.15 0.08 0.1 0.1 0.1 0.06 0.1 0.05 0.04 0.05 0.05 0.02 0.05 0 0 0 1 3 5 7 9 11 13 15 17 19 0 0 1 3 5 7 9 11 13 15 17 19 -0.02 1 3 5 7 9 11 13 15 17 19 -0.05 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 -0.05 -0.04 -0.05 -0.06 -0.05 -0.1 -0.1 -0.08 -0.1 -0.15 -0.1 -0.15 -0.1 -0.15

0.15 1996 0.15 2001 0.15 2006 2011 2016

0.1 0.15 0.2 0.1 0.1 0.15 0.05 0.05 0.1 0.1 0.05 0.05 0 0 0.05 0 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 0 1 3 5 7 9 11 13 15 17 19 -0.05 -0.05 1 3 5 7 9 11 13 15 17 19 0 -0.05 -0.1 -0.05 1 3 5 7 9 11 13 15 17 19 -0.1 -0.1 -0.05 -0.15 -0.15 -0.15 -0.1 -0.1 f_obs f_est m_obs m_est

0.15 0.15 1997 0.15 2002 0.15 2007 2012 0.1 0.1 0.1 0.1

0.05 0.05 0.05 0.05 0 0 1 3 5 7 9 11 13 15 17 19 0 0 1 4 7 10 13 16 19 -0.05 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 -0.05 -0.05 -0.05 -0.1 -0.1

-0.15 -0.1 -0.1 -0.15

0.12 0.1 0.14 1998 0.15 2003 2013 0.1 2008 0.12 0.08 0.1 0.1 0.05 0.08 0.06 0.05 0.06 0.04 0 0.04 0 0.02 1 3 5 7 9 11 13 15 17 19 0.02 1 3 5 7 9 11 13 15 17 19 0 -0.05 0 -0.05 1 3 5 7 9 11 13 15 17 19 -0.02 1 3 5 7 9 11 13 15 17 19 -0.02 -0.04 -0.1 -0.04 -0.1 -0.06 -0.06 -0.08 -0.15 -0.08 -0.15 01

Figure 4.17 (continued).

Survey Survey Survey Survey Survey Survey Survey

1 0.1 0.1 0.2 9 0.2 8 0 1979 1984 1989 0.15 1994 0.15 1999 0.15 2004 2009 0.08 0.08 0.15 0.15 0 .1 0.06 females 0.06 0.1 0.1 0.08 0.1 0.04 0.1 0.1 0.06 0.04 0.05 0.05 0.04 0.02 0.02 0.05 0.05 0.05 0.02 0 0 0 0 0 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 0 0 0 - 0. 0 2 -0.02 1 3 5 7 9 11 13 15 17 19 -0.02 1 3 5 7 9 11 13 15 17 19 -0.05 -0.05 1 3 5 7 9 11 13 15 17 19 - 0. 0 4 -0.04 -0.04 -0.05 -0.05 - 0. 0 6 -0.05 -0.06 males -0.1 -0.1 - 0. 0 8 -0.06 -0.1 -0.1 - 0. 1 -0.08 -0.08 -0.1 -0.15 -0.15 - 0. 1 2 -0.1 -0.15 -0.15

1 9 0.15 8 0.1 0 1980 0.1 1985 0.2 1990 0.15 1995 0.1 2000 0.1 2005 2010 0.08 0.08 0 .1 0.08 0.15 0.1 0.06 0.08 0.06 0.1 0.06 0.05 0.04 0.06 0.1 0.04 0.05 0.02 0.04 0.04 0.05 0.02 0.05 0 0.02 0 0.02 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 0 0 0 -0. 02 0 0 1 3 5 7 9 11 13 15 17 19 0 -0.02 1 3 5 7 9 11 13 15 17 19 - 0. 0 2 -0.05 -0. 04 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 -0.02 1 3 5 7 9 11 13 15 17 19 - 0. 0 4 -0.04 -0.05 -0. 06 -0.05

- 0. 0 6 -0.04 -0. 08 -0.05 -0.06 -0.1 - 0. 0 8 -0.1 -0.1 -0. 1 -0.06 -0.08

- 0. 1 -0. 12 -0.08 -0.15 -0.1 -0.1 -0.15 - 0. 1 2 -0.15

1 0.15 9 8 0.1 0 1981 1986 1991 0.1 1996 0.15 2001 0.1 2006 2011 0.15 0.1 0.1 0 .1 0.08 0.08 0.1 0.08 0.05 0.1 0.06 0.05 0.06 0.06 0.05 0.05 0.04 0.04 0.04 0.05 0 0.02 0.02 0 1 3 5 7 9 11 13 15 17 19 0.02 0 0 0 1 3 5 7 9 11 13 15 17 19 0 0 1 3 5 7 9 11 13 15 17 19 0 -0.05 - 0. 0 2 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 -0.05 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 -0.02 -0.05 -0.02 - 0. 0 4 -0.05 -0.04 - 0. 0 6 -0.1 -0.04 -0.05 -0.1 -0.1 - 0. 0 8 -0.06 -0.1 -0.06 - 0. 1 -0.08 -0.15 -0.15 -0.15 -0.08 - 0. 1 2 -0.15 -0.1 -0.1

1 0.15 9 8 0.15 0 0.1 1982 0.15 1987 1992 0.1 1997 0.15 2002 0.15 2007 2012 0.08 0.1 0.08 0 .1 0.1 0.1 0.1 0.08 0.06 0.06 0.1

0.06 0.04 0.05 0.04 0.05 0.05 0.04 0.02 0.02 0.05 0.05 0.02 0 0 0 0 0 0 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 -0.02 - 0. 0 2 -0.02 0 -0.05 0 -0.05 -0.05 1 3 5 7 9 11 13 15 17 19 - 0. 0 4 -0.04 -0.04 1 3 5 7 9 11 13 15 17 19 - 0. 0 6 -0.06 -0.06 -0.05 -0.1 -0.1 -0.1 -0.05 - 0. 0 8 -0.08 -0.08

- 0. 1 -0.1 -0.15 -0.15 -0.1 -0.15 -0.1 - 0. 1 2 -0.1

0.1 0.1 1983 0.2 1988 0.15 1993 0.12 1998 0.15 2003 2008 2013 0.1 0.1 0.15 0.1 0.08 0.1 0.05 0.05 0.05 0.1 0.06 0.05 0.05 0.04 0.05 0 0.02 0 0 0 1 3 5 7 9 11 13 15 17 19 0 0 1 3 5 7 9 11 13 15 17 19 0 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 -0.02 1 3 5 7 9 11 13 15 17 19 -0.05 -0.05 -0.05 -0.05 -0.04 -0.05 -0.05 -0.1 -0.06 -0.1 -0.1 -0.1 -0.08 -0.15 -0.15 -0.1 -0.15 -0.15 -0.1 -0.1

Figure 4.17 (continued).

Survey Survey Survey Survey

0.2 0.1 0.15 1999 0.15 2004 2009 2014 0.15 0.1 0.1 0.05 0.1 0.05 0.05 0.05 0 0 0 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 0 1 3 5 7 9 11 13 15 17 19 -0.05 -0.05 1 3 5 7 9 11 13 15 17 19 -0.05 -0.05 -0.1 -0.1 -0.1 -0.15 -0.15 -0.15 -0.1

0.15 0.1 2000 0.1 2005 2010 2015 0.08 0.1 0.06 0.05 0.1 0.04 0.05 0.02 0 0.05 1 3 5 7 9 11 13 15 17 19 0 0 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 -0.02 -0.05 0 -0.04 -0.05 1 3 5 7 9 11 13 15 17 19 -0.06 -0.1 -0.05 -0.08 -0.1 -0.1 -0.15 -0.15 -0.1

0.1 0.15 2001 0.1 2006 2011 0.1 2016 0.08 0.1 0.06 0.05 0.05 0.05 0.04

0.02 0 0 0 1 3 5 7 9 11 13 15 17 19 0 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 -0.05 -0.02 -0.05 -0.04 -0.05 -0.1 -0.06 -0.1 -0.15 -0.08 -0.1

0.15 0.15 2002 0.15 2007 2012

0.1 0.1 0.1

0.05 0.05 0.05 0 1 3 5 7 9 11 13 15 17 19 0 0 -0.05 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 -0.05 -0.1 -0.05

-0.15 -0.1 -0.1

0.1 0.1 0.15 2003 2008 2013

0.1 0.05 0.05 0.05

0 0 0 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 1 3 5 7 9 11 13 15 17 19 -0.05 -0.05 -0.05 -0.1

-0.15 -0.1 -0.1

Figure 4.17 (continued).

survey fit with fixed and temperature modified q 4000

3500 observed q_temp estimate q fixed at 0.9542 3000

2500

2000

1500

1000

500

0 1980 1985 1990 1995 2000 2005 2010 2015

Figure 4.18.--Comparison of the fit to the survey biomass using a fixed q and the q-bottom temperature relationship.

4.5 age 5 recruitment 4

3.5

3

2.5

2

1.5 recruitment (billions) recruitment 1

0.5

0 49 52 55 58 61 64 67 70 73 76 79 82 85 88 91 94 97 0 3 6 9 12 year class

Figure 4.19--Year class strength of age 5 yellowfin sole estimated by the stock assessment model. The dotted line is the average of the estimates from 62 years of recruitment.

Fmsy Bmsy 500 600

500 400

400 300

300 200 frequency

frequency 200 100 100 0 0 0 500 1000 0 0.1 Fmsy 0.2 0.3 female spawning biomass (1,000s t) age 6 plus biomass 2018 age 6+ biomass 2019 700 700 600 600 500 500 400 400 300

frequency 300 200 200 100 100 0 0 1000 2000 3000 4000 0 total biomass 6+ (1,000s t) 0 1000 2000 3000 4000 2018 female spawning biomass mean log recruitment

700 600 600 500

500 400 400 300 300 frequency frequency 200 200 100 100 0 0 0 500 1000 1500 0 0.5 1 1.5 female spawning biomass (1,000s t) log recruitment Figure 4.20.--Posterior distributions of some important parameters estimated by the preferred stock assessment model (from mcmc integration).

retrospective model results 1200

1000

800

600

400

200

0 1954 1964 1974 1984 1994 2004 2014

2016 2015 2014 2013 2011 2010 2009 2008

Figure 4.21—Retrospective plot of yellowfin sole female spawning biomass estimates (1,000s t), 2008- 2016, from the recommended assessment model.

Projection at average F from most

1200 recent 5 years

1000

800

600

400

200

0 2017 2019 2021 2023 2025 2027 2029 Bmsy LowCI_SSB Mean_SSB UpperCI_SSB

Figure 4.22. Projection of yellowfin sole female spawning biomass (1,000s t) at the average full- selection F from the past 5 years (0.104) through 2030 with B40% and Bmsy levels indicated.

yellowfin sole 0.2

0.15 Bmsy

0.1 1975

0.05 2018 Fishing mortality rate mortality Fishing

0 0 250000 500000 750000 1000000 1250000 female spawning biomass

Figure 4.23. Phase plane figure of the time-series of yellowfin sole female spawning biomass relative to the harvest control rule with 1975 and 2018 indicated.

Appendix

IPHC research catch of yellowfin sole number weight (kg) 2007 707 502 2008 0 0 2009 0 0 2010 898 741